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href="https://az.wikipedia.org/wiki/PlanetMath" title="PlanetMath – Azerbaijani" lang="az" hreflang="az" data-title="PlanetMath" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/PlanetMath" title="PlanetMath – Catalan" lang="ca" hreflang="ca" data-title="PlanetMath" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/PlanetMath" title="PlanetMath – German" lang="de" hreflang="de" data-title="PlanetMath" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/PlanetMath" title="PlanetMath – Greek" lang="el" hreflang="el" data-title="PlanetMath" data-language-autonym="Ελληνικά" data-language-local-name="Greek" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/PlanetMath" title="PlanetMath – Spanish" lang="es" hreflang="es" data-title="PlanetMath" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D9%BE%D9%84%D9%86%D8%AA%E2%80%8C%D9%85%D8%AB" title="پلنت‌مث – Persian" lang="fa" hreflang="fa" data-title="پلنت‌مث" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/PlanetMath" title="PlanetMath – French" lang="fr" hreflang="fr" data-title="PlanetMath" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%ED%94%8C%EB%9E%98%EB%8B%9B%EB%A7%A4%EC%8A%A4" title="플래닛매스 – Korean" lang="ko" hreflang="ko" data-title="플래닛매스" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/PlanetMath" title="PlanetMath – Indonesian" lang="id" hreflang="id" data-title="PlanetMath" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/PlanetMath" title="PlanetMath – Italian" lang="it" hreflang="it" data-title="PlanetMath" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/PlanetMath" title="PlanetMath – Dutch" lang="nl" hreflang="nl" data-title="PlanetMath" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/PlanetMath" title="PlanetMath – Japanese" lang="ja" hreflang="ja" data-title="PlanetMath" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/PlanetMath" title="PlanetMath – Polish" lang="pl" hreflang="pl" data-title="PlanetMath" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/PlanetMath" title="PlanetMath – Portuguese" lang="pt" hreflang="pt" data-title="PlanetMath" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/PlanetMath" title="PlanetMath – Romanian" lang="ro" hreflang="ro" data-title="PlanetMath" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/PlanetMath" title="PlanetMath – Russian" lang="ru" hreflang="ru" data-title="PlanetMath" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/PlanetMath" title="PlanetMath – Slovenian" lang="sl" hreflang="sl" data-title="PlanetMath" data-language-autonym="Slovenščina" data-language-local-name="Slovenian" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-ckb mw-list-item"><a href="https://ckb.wikipedia.org/wiki/%D9%BE%D9%84%DB%95%D9%86%DB%8E%D8%AA_%D9%85%D8%A7%D8%AA" title="پلەنێت مات – Central Kurdish" lang="ckb" hreflang="ckb" data-title="پلەنێت مات" data-language-autonym="کوردی" data-language-local-name="Central Kurdish" class="interlanguage-link-target"><span>کوردی</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Planetmath" title="Planetmath – Swedish" lang="sv" hreflang="sv" data-title="Planetmath" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/PlanetMath" title="PlanetMath – Turkish" lang="tr" hreflang="tr" data-title="PlanetMath" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/PlanetMath" title="PlanetMath – Ukrainian" lang="uk" hreflang="uk" data-title="PlanetMath" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/PlanetMath" title="PlanetMath – Vietnamese" lang="vi" hreflang="vi" 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class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Online encyclopedia</div> <style data-mw-deduplicate="TemplateStyles:r1257001546">.mw-parser-output .infobox-subbox{padding:0;border:none;margin:-3px;width:auto;min-width:100%;font-size:100%;clear:none;float:none;background-color:transparent}.mw-parser-output .infobox-3cols-child{margin:auto}.mw-parser-output .infobox .navbar{font-size:100%}@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme) div:not(.notheme){background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table tr{display:table-row!important}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}</style><table class="infobox vcard"><caption class="infobox-title fn org">PlanetMath</caption><tbody><tr><td colspan="2" class="infobox-image"><span typeof="mw:File"><a href="/wiki/File:Pmlogo.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Pmlogo.png/182px-Pmlogo.png" decoding="async" width="182" height="30" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Pmlogo.png/273px-Pmlogo.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/65/Pmlogo.png/364px-Pmlogo.png 2x" data-file-width="394" data-file-height="65" /></a></span></td></tr><tr><th scope="row" class="infobox-label"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Type of site</div></th><td class="infobox-data"><a href="/wiki/Online_encyclopedia" title="Online encyclopedia">Online encyclopedia</a></td></tr><tr><th scope="row" class="infobox-label">Available in</th><td class="infobox-data"><a href="/wiki/English_language" title="English language">English</a></td></tr><tr><th scope="row" class="infobox-label">Owner</th><td class="infobox-data">PlanetMath.org, Ltd.</td></tr><tr><th scope="row" class="infobox-label">Created by</th><td class="infobox-data"><style data-mw-deduplicate="TemplateStyles:r1126788409">.mw-parser-output .plainlist ol,.mw-parser-output .plainlist ul{line-height:inherit;list-style:none;margin:0;padding:0}.mw-parser-output .plainlist ol li,.mw-parser-output .plainlist ul li{margin-bottom:0}</style><div class="plainlist"><ul><li>Nathan Egge</li><li>Aaron Krowne</li></ul></div></td></tr><tr><th scope="row" class="infobox-label">URL</th><td class="infobox-data url"><span class="url"><a rel="nofollow" class="external text" href="https://planetmath.org/">planetmath<wbr />.org</a></span></td></tr><tr><th scope="row" class="infobox-label">Commercial</th><td class="infobox-data">No</td></tr><tr><th scope="row" class="infobox-label">Registration</th><td class="infobox-data"><a href="/wiki/GitHub" title="GitHub">GitHub</a> account required to edit sources via pull request</td></tr><tr><th scope="row" class="infobox-label">Current status</th><td class="infobox-data category">Inactive</td></tr><tr><th scope="row" class="infobox-label"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Content license</div></th><td class="infobox-data"><a href="/wiki/CC_BY-SA" class="mw-redirect" title="CC BY-SA">CC BY-SA</a></td></tr></tbody></table> <p><b>PlanetMath</b> is a <a href="/wiki/Free_content" title="Free content">free</a>, collaborative, <a href="/wiki/Mathematics" title="Mathematics">mathematics</a> <a href="/wiki/Online_encyclopedia" title="Online encyclopedia">online encyclopedia</a>. Intended to be comprehensive, the project is currently hosted by the <a href="/wiki/University_of_Waterloo" title="University of Waterloo">University of Waterloo</a>. The site is owned by a US-based nonprofit corporation, "PlanetMath.org, Ltd".<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>PlanetMath was started when the popular free online mathematics encyclopedia <a href="/wiki/MathWorld" title="MathWorld">MathWorld</a> was temporarily taken offline for 12 months by a court injunction as a result of the <a href="/wiki/CRC_Press" title="CRC Press">CRC Press</a> lawsuit against the <a href="/wiki/Wolfram_Research" title="Wolfram Research">Wolfram Research</a> company and its employee (and MathWorld's author) <a href="/wiki/Eric_Weisstein" class="mw-redirect" title="Eric Weisstein">Eric Weisstein</a>. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Materials">Materials</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=PlanetMath&action=edit&section=1" title="Edit section: Materials"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The main PlanetMath focus is on <a href="/wiki/Encyclopedia" title="Encyclopedia">encyclopedic</a> entries. It formerly operated a self-hosted forum, but now encourages discussion via <a href="/wiki/Gitter" title="Gitter">Gitter</a>. </p><p>An all-inclusive PlanetMath <i>Free Encyclopedia</i> book of 2,300 pages is available for the encyclopedia contents up to 2006 as a free download PDF file.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Content_development_model">Content development model</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=PlanetMath&action=edit&section=2" title="Edit section: Content development model"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>PlanetMath implements a specific content creation system called <i>authority model</i>.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p><p>An author who starts a new article becomes its <i>owner</i>, that is the only person authorized to edit that article. Other users may add corrections and discuss improvements but the resulting modifications of the article, if any, are always made by the owner. However, if there are long lasting unresolved corrections, the ownership can be removed. More precisely, after two weeks the system starts to remind the owner by mail; at six weeks any user can "adopt" the article; at eight weeks the ownership of the entry is completely removed (and such an entry is called "orphaned"). </p><p>To make the development more smooth, the owner may also choose to grant editing rights to other individuals or groups. </p><p>The user can explicitly create links to other articles, and the system also automatically turns certain words into links to the defining articles. The topic area of every article is classified by the <a href="/wiki/Mathematics_Subject_Classification" title="Mathematics Subject Classification">Mathematics Subject Classification</a> (MSC) of the <a href="/wiki/American_Mathematical_Society" title="American Mathematical Society">American Mathematical Society</a> (AMS). </p><p>The site is supervised by the Content Committee. Its basic mission is to <i>maintain the integrity and quality of the mathematical content and organization of PlanetMath.</i><sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> As defined in its Charter, the tasks of the Committee include: </p> <ul><li>Developing/maintaining the standards for PlanetMath content</li> <li>Improving individual PlanetMath entries in its Encyclopedia, Book, Paper, and Exposition)</li> <li>Developing topic areas</li> <li>Developing/improving site and user documentation</li> <li>Managing the PlanetMath Request list and Unproved Theorems list</li> <li>Improving categorization and other meta-attributes of entries.</li> <li>Developing software recommendations for improved content authoring and editorial functions.</li></ul> <div class="mw-heading mw-heading3"><h3 id="Technical_details">Technical details</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=PlanetMath&action=edit&section=3" title="Edit section: Technical details"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>PlanetMath content is licensed under the <a href="/wiki/Copyleft" title="Copyleft">copyleft</a> <a href="/wiki/Creative_Commons_Attribution/Share-Alike_License" class="mw-redirect" title="Creative Commons Attribution/Share-Alike License">Creative Commons Attribution/Share-Alike License</a>. All content is written in <a href="/wiki/LaTeX" title="LaTeX">LaTeX</a>, a typesetting system popular among mathematicians because of its support of the technical needs of mathematical typesetting and its high-quality output. </p><p>PlanetMath originally used software written in <a href="/wiki/Perl" title="Perl">Perl</a> and running on <a href="/wiki/Linux" title="Linux">Linux</a> and the web server <a href="/wiki/Apache_server" class="mw-redirect" title="Apache server">Apache</a>. It was known as <i>Noösphere</i> and has been released under the free <a href="/wiki/BSD_License" class="mw-redirect" title="BSD License">BSD License</a>. PlanetMath retired Noösphere in favor of another piece of software called <i>Planetary</i>, implemented with <a href="/wiki/Drupal" title="Drupal">Drupal</a>. </p> <div class="mw-heading mw-heading3"><h3 id="Related_projects">Related projects</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=PlanetMath&action=edit&section=4" title="Edit section: Related projects"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Encyclopedic content and bibliographic materials related to <a href="/wiki/Physics" title="Physics">physics</a>, <a href="/wiki/Mathematics" title="Mathematics">mathematics</a> and <a href="/wiki/Mathematical_physics" title="Mathematical physics">mathematical physics</a> are developed by <a href="/wiki/PlanetPhysics" title="PlanetPhysics">PlanetPhysics</a>. The site, launched in 2005, uses similar software (Noosphere), but a significantly different moderation model with emphasis on current research in physics and peer review.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=PlanetMath&action=edit&section=5" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/ArXiv" title="ArXiv">arXiv</a></li> <li><a href="/wiki/CogPrints" title="CogPrints">CogPrints</a></li> <li><a href="/wiki/List_of_online_encyclopedias" title="List of online encyclopedias">List of online encyclopedias</a></li> <li><a href="/wiki/MathWorld" title="MathWorld">MathWorld</a></li> <li><a href="/wiki/MathOverflow" title="MathOverflow">MathOverflow</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=PlanetMath&action=edit&section=6" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output 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.id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://planetmath.org/?op%3Dgetobj%26from%3Dcollab%26id%3D35#SECTION00021000000000000000">"Archived copy"</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20160826090901/http://planetmath.org/?op=getobj&from=collab&id=35">Archived</a> from the original on 2016-08-26<span class="reference-accessdate">. Retrieved <span class="nowrap">2009-05-15</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Archived+copy&rft_id=http%3A%2F%2Fplanetmath.org%2F%3Fop%253Dgetobj%2526from%253Dcollab%2526id%253D35%23SECTION00021000000000000000&rfr_id=info%3Asid%2Fen.wikipedia.org%3APlanetMath" class="Z3988"></span><span class="cs1-maint citation-comment"><code class="cs1-code">{{<a href="/wiki/Template:Cite_web" title="Template:Cite web">cite web</a>}}</code>: CS1 maint: archived copy as title (<a href="/wiki/Category:CS1_maint:_archived_copy_as_title" title="Category:CS1 maint: archived copy as title">link</a>)</span>, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://planetmath.org/?op%3Dabout">"Planetmath.org | Math for the people, by the people"</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20160611023918/http://planetmath.org/?op=about">Archived</a> from the original on 2016-06-11<span class="reference-accessdate">. Retrieved <span class="nowrap">2008-05-02</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Planetmath.org+%26%23124%3B+Math+for+the+people%2C+by+the+people&rft_id=http%3A%2F%2Fplanetmath.org%2F%3Fop%253Dabout&rfr_id=info%3Asid%2Fen.wikipedia.org%3APlanetMath" class="Z3988"></span> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20080509123133/http://aux.planetmath.org/doc/donate.html">"Helping PlanetMath"</a>. Archived from <a rel="nofollow" class="external text" href="https://aux.planetmath.org/doc/donate.html">the original</a> on 2008-05-09<span class="reference-accessdate">. Retrieved <span class="nowrap">2009-05-19</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Helping+PlanetMath&rft_id=http%3A%2F%2Faux.planetmath.org%2Fdoc%2Fdonate.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3APlanetMath" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://planetphysics.org/?op=getobj&from=books&id=207">PlanetMath "<i>Free Encyclopedia</i>" book</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20160620044430/http://planetphysics.org/?op=getobj&from=books&id=207">Archived</a> June 20, 2016, at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a> based on 2004-2005 content of PlanetMath</span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://planetmath.org/?op=getobj&from=collab&id=34">Noosphere's</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20160304034756/http://planetmath.org/?op=getobj&from=collab&id=34">Archived</a> March 4, 2016, at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a> authority model</span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFUsername_*" class="citation web cs1">Username *. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20101126222624/http://planetmath.org/?op=getobj&from=collab&id=130">"ContentCommittee Charter"</a>. Planetmath.org. Archived from <a rel="nofollow" class="external text" href="https://planetmath.org/?op=getobj&from=collab&id=130">the original</a> on 2010-11-26<span class="reference-accessdate">. Retrieved <span class="nowrap">2013-09-06</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=ContentCommittee+Charter&rft.pub=Planetmath.org&rft.au=Username+%2A&rft_id=http%3A%2F%2Fplanetmath.org%2F%3Fop%3Dgetobj%26from%3Dcollab%26id%3D130&rfr_id=info%3Asid%2Fen.wikipedia.org%3APlanetMath" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://planetphysics.org/">PlanetPhysics.org</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20090225121156/http://planetphysics.org/">Archived</a> February 25, 2009, at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=PlanetMath&action=edit&section=7" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><span class="official-website"><span class="url"><a rel="nofollow" class="external text" href="https://planetmath.org">Official website</a></span></span> <span class="mw-valign-text-top" typeof="mw:File/Frameless"><a href="https://www.wikidata.org/wiki/Q1130535#P856" title="Edit this at Wikidata"><img alt="Edit this at Wikidata" src="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/10px-OOjs_UI_icon_edit-ltr-progressive.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/15px-OOjs_UI_icon_edit-ltr-progressive.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/20px-OOjs_UI_icon_edit-ltr-progressive.svg.png 2x" data-file-width="20" data-file-height="20" /></a></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20090225121156/http://planetphysics.org/">"PlanetPhysics"</a>. Archived from <a rel="nofollow" class="external text" href="http://planetphysics.org">the original</a> on February 25, 2009.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=PlanetPhysics&rft_id=http%3A%2F%2Fplanetphysics.org&rfr_id=info%3Asid%2Fen.wikipedia.org%3APlanetMath" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFKlemm2005" class="citation web cs1">Klemm, Aaron E. (February 16, 2005). <a rel="nofollow" class="external text" href="http://freesoftwaremagazine.com/articles/wiki_value/">"Motivation and value of free resources: Wikipedia and Planetmath show the way"</a>. Free Software magazine.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Motivation+and+value+of+free+resources%3A+Wikipedia+and+Planetmath+show+the+way&rft.pub=Free+Software+magazine&rft.date=2005-02-16&rft.aulast=Klemm&rft.aufirst=Aaron+E.&rft_id=http%3A%2F%2Ffreesoftwaremagazine.com%2Farticles%2Fwiki_value%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3APlanetMath" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFKlemm2005" class="citation journal cs1"><a rel="nofollow" class="external text" href="http://www.dvara.net/HK/issue.pdf">"Motivation and value of free resources"</a> <span class="cs1-format">(PDF)</span>. <i>Free Software Magazine</i> (1): <span class="nowrap">52–</span>56. February 2005.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Free+Software+Magazine&rft.atitle=Motivation+and+value+of+free+resources&rft.issue=1&rft.pages=%3Cspan+class%3D%22nowrap%22%3E52-%3C%2Fspan%3E56&rft.date=2005-02&rft.aulast=Klemm&rft.aufirst=Aaron+E.&rft_id=http%3A%2F%2Fwww.dvara.net%2FHK%2Fissue.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3APlanetMath" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation journal cs1"><a rel="nofollow" class="external text" href="https://doi.org/10.1126%2Fscience.308.5729.1721e">"Web Projects: Grassroots Math Guide"</a>. <i>Science</i>. Netwatch. <b>308</b> (5729). <a href="/wiki/American_Association_for_the_Advancement_of_Science" title="American Association for the Advancement of Science">AAAS</a>: 1721. 17 June 2005. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1126%2Fscience.308.5729.1721e">10.1126/science.308.5729.1721e</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Science&rft.atitle=Web+Projects%3A+Grassroots+Math+Guide&rft.volume=308&rft.issue=5729&rft.pages=1721&rft.date=2005-06-17&rft_id=info%3Adoi%2F10.1126%2Fscience.308.5729.1721e&rft_id=https%3A%2F%2Fdoi.org%2F10.1126%252Fscience.308.5729.1721e&rfr_id=info%3Asid%2Fen.wikipedia.org%3APlanetMath" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFLange2008" class="citation book cs1">Lange, Christoph (2008). "SWiM – A Semantic Wiki for Mathematical Knowledge Management". <i>The Semantic Web: Research and Applications</i>. European Semantic Web Conference (ESWC). 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"Archives, mathematics encyclopaedia, dancing robots, ASC". <i>Kybernetes</i>. <b>37</b> (9/10): <span class="nowrap">1466–</span>1468. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1108%2F03684920810907805">10.1108/03684920810907805</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Kybernetes&rft.atitle=Archives%2C+mathematics+encyclopaedia%2C+dancing+robots%2C+ASC&rft.volume=37&rft.issue=9%2F10&rft.pages=%3Cspan+class%3D%22nowrap%22%3E1466-%3C%2Fspan%3E1468&rft.date=2008&rft_id=info%3Adoi%2F10.1108%2F03684920810907805&rft.aulast=Andrew&rft.aufirst=Alex+M.&rfr_id=info%3Asid%2Fen.wikipedia.org%3APlanetMath" class="Z3988"></span></li></ul>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?useformat=desktop&type=1x1&usesul3=0" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=PlanetMath&oldid=1273117817">https://en.wikipedia.org/w/index.php?title=PlanetMath&oldid=1273117817</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Categories</a>: <ul><li><a href="/wiki/Category:Mathematics_websites" title="Category:Mathematics websites">Mathematics websites</a></li><li><a href="/wiki/Category:Online_encyclopedias" title="Category:Online encyclopedias">Online encyclopedias</a></li><li><a href="/wiki/Category:Wiki_communities" title="Category:Wiki communities">Wiki communities</a></li><li><a href="/wiki/Category:Canadian_online_encyclopedias" title="Category:Canadian online encyclopedias">Canadian online encyclopedias</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:CS1_maint:_archived_copy_as_title" title="Category:CS1 maint: archived copy as title">CS1 maint: archived copy as title</a></li><li><a href="/wiki/Category:Webarchive_template_wayback_links" title="Category:Webarchive template wayback links">Webarchive template wayback links</a></li><li><a href="/wiki/Category:Articles_with_short_description" title="Category:Articles with short description">Articles with short description</a></li><li><a href="/wiki/Category:Short_description_matches_Wikidata" title="Category:Short description matches Wikidata">Short description matches Wikidata</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 31 January 2025, at 20:36<span class="anonymous-show"> (UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. 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