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class="mw-body-content"><script>function mfTempOpenSection(id){var block=document.getElementById("mf-section-"+id);block.className+=" open-block";block.previousSibling.className+=" open-block";}</script><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><section class="mf-section-0" id="mf-section-0"> <style data-mw-deduplicate="TemplateStyles:r1251242444">.mw-parser-output .ambox{border:1px solid #a2a9b1;border-left:10px solid #36c;background-color:#fbfbfb;box-sizing:border-box}.mw-parser-output .ambox+link+.ambox,.mw-parser-output .ambox+link+style+.ambox,.mw-parser-output .ambox+link+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+style+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+link+.ambox{margin-top:-1px}html body.mediawiki .mw-parser-output .ambox.mbox-small-left{margin:4px 1em 4px 0;overflow:hidden;width:238px;border-collapse:collapse;font-size:88%;line-height:1.25em}.mw-parser-output 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ambox-Refimprove" role="presentation"><tbody><tr><td class="mbox-text"><div class="mbox-text-span">This article <b>needs additional citations for <a href="/wiki/Wikipedia:Verifiability" title="Wikipedia:Verifiability">verification</a></b>.<span class="hide-when-compact"> Please help <a href="/wiki/Special:EditPage/Z39.50" title="Special:EditPage/Z39.50">improve this article</a> by <a href="/wiki/Help:Referencing_for_beginners" title="Help:Referencing for beginners">adding citations to reliable sources</a>. Unsourced material may be challenged and removed.<br><small><span class="plainlinks"><i>Find sources:</i> <a rel="nofollow" class="external text" href="https://www.google.com/search?as_eq=wikipedia&q=%22Z39.50%22">"Z39.50"</a> – <a rel="nofollow" class="external text" href="https://www.google.com/search?tbm=nws&q=%22Z39.50%22+-wikipedia&tbs=ar:1">news</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?&q=%22Z39.50%22&tbs=bkt:s&tbm=bks">newspapers</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?tbs=bks:1&q=%22Z39.50%22+-wikipedia">books</a> <b>·</b> <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar?q=%22Z39.50%22">scholar</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.jstor.org/action/doBasicSearch?Query=%22Z39.50%22&acc=on&wc=on">JSTOR</a></span></small></span> <span class="date-container"><i>(<span class="date">November 2021</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <p><b>Z39.50</b> is an <a href="/wiki/International_standard" title="International standard">international standard</a> <a href="/wiki/Client%E2%80%93server" class="mw-redirect" title="Client–server">client–server</a>, <a href="/wiki/Application_layer" title="Application layer">application layer</a> <a href="/wiki/Communications_protocol" class="mw-redirect" title="Communications protocol">communications protocol</a> for searching and retrieving information from a <a href="/wiki/Database" title="Database">database</a> over a <a href="/wiki/TCP/IP" class="mw-redirect" title="TCP/IP">TCP/IP</a> <a href="/wiki/Computer_network" title="Computer network">computer network</a>, developed and maintained by the <a href="/wiki/Library_of_Congress" title="Library of Congress">Library of Congress</a>. It is covered by <a href="/wiki/American_National_Standards_Institute" title="American National Standards Institute">ANSI</a>/<a href="/wiki/NISO" class="mw-redirect" title="NISO">NISO</a> standard Z39.50, and <a href="/wiki/International_Organization_for_Standardization" title="International Organization for Standardization">ISO</a> standard 23950. </p><p>Z39.50 is widely used<sup class="noprint Inline-Template" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Manual_of_Style/Dates_and_numbers#Chronological_items" title="Wikipedia:Manual of Style/Dates and numbers"><span title="The time period mentioned near this tag is ambiguous. (May 2018)">as of?</span></a></i>]</sup> in <a href="/wiki/Library" title="Library">library</a> environments, for <a href="/wiki/Interlibrary_loan" title="Interlibrary loan">interlibrary catalogue search and loan</a>, often incorporated into <a href="/wiki/Integrated_library_system" title="Integrated library system">integrated library systems</a> and personal <a href="/wiki/Reference_management_software" title="Reference management software">bibliographic reference software</a>, and social media such as <a href="/wiki/LibraryThing" title="LibraryThing">LibraryThing</a>. </p><p>Work on the Z39.50 protocol began in the 1970s, and led to successive versions in 1988, 1992, 1995 and 2003. The <a href="/wiki/Contextual_Query_Language" title="Contextual Query Language">Contextual Query Language</a> (formerly called the Common Query Language)<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> is based on Z39.50 semantics. </p> <div id="toc" class="toc" role="navigation" aria-labelledby="mw-toc-heading"><input type="checkbox" role="button" id="toctogglecheckbox" class="toctogglecheckbox" style="display:none"><div class="toctitle" lang="en" dir="ltr"><h2 id="mw-toc-heading">Contents</h2><span class="toctogglespan"><label class="toctogglelabel" for="toctogglecheckbox"></label></span></div> <ul> <li class="toclevel-1 tocsection-1"><a href="#Search_syntax"><span class="tocnumber">1</span> <span class="toctext">Search syntax</span></a></li> <li class="toclevel-1 tocsection-2"><a href="#Modernization_efforts"><span class="tocnumber">2</span> <span class="toctext">Modernization efforts</span></a></li> <li class="toclevel-1 tocsection-3"><a href="#Firewall_information"><span class="tocnumber">3</span> <span class="toctext">Firewall information</span></a></li> <li class="toclevel-1 tocsection-4"><a href="#See_also"><span class="tocnumber">4</span> <span class="toctext">See also</span></a></li> <li class="toclevel-1 tocsection-5"><a href="#References"><span class="tocnumber">5</span> <span class="toctext">References</span></a></li> <li class="toclevel-1 tocsection-6"><a href="#External_links"><span class="tocnumber">6</span> <span class="toctext">External links</span></a></li> </ul> </div> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(1)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="Search_syntax">Search syntax</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Z39.50&action=edit&section=1" title="Edit section: Search syntax" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-1 collapsible-block" id="mf-section-1"> <p>The protocol supports search, retrieval, sort, and browse. Search queries contain attributes, typically from the bib-1 attribute set which defines six attributes to specify information searches on the server computer: use, relation, position, structure, truncation, completeness. The syntax of Z39.50 allows for very complex queries. </p><p>In practice, the functional complexity is limited by the uneven implementations by developers and commercial vendors. The syntax of Z39.50 is abstracted from the underlying database structure. For example, if the client specifies an author search using attribute 1003, the server must determine how to map that search to the indexes it contains. This allows Z39.50 queries to be formulated without knowing anything about the target database, but it also means that results for the same query can vary widely among different servers. One server may have an author index and another may use its index of personal names, whether they are authors or not. A third may have no name index and fall back on its keyword index, and yet another may have no suitable index and return an error. </p><p>An attempt to remedy the inconsistency is the <a href="/wiki/Bath_Profile" title="Bath Profile">Bath Profile</a> (named after <a href="/wiki/Bath,_Somerset" title="Bath, Somerset">Bath</a>, England, where the <a href="/wiki/Working_group" title="Working group">working group</a> first met in 1999). This document rigidly specifies the search syntax to employ for common bibliographic searches, and the expected response of Bath-compliant servers. Implementation of the Bath Profile has been slow but is gradually improving the Z39.50 landscape<sup class="noprint Inline-Template" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Manual_of_Style/Dates_and_numbers#Chronological_items" title="Wikipedia:Manual of Style/Dates and numbers"><span title="The time period mentioned near this tag is ambiguous. (May 2018)">as of?</span></a></i>]</sup>. The Bath Profile is maintained by <a href="/wiki/Library_and_Archives_Canada" title="Library and Archives Canada">Library and Archives Canada</a>. </p> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(2)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="Modernization_efforts">Modernization efforts</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Z39.50&action=edit&section=2" title="Edit section: Modernization efforts" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-2 collapsible-block" id="mf-section-2"> <p>Z39.50 is a pre-<a href="/wiki/World_Wide_Web" title="World Wide Web">Web</a> technology, and various working groups are attempting to update it to fit better into the modern environment. These attempts fall under the designation ZING (Z39.50 International: Next Generation), and pursue various strategies. </p><p>The successors to Z39.50 are the twin protocols <a href="/wiki/Search/Retrieve_via_URL" title="Search/Retrieve via URL">SRU</a>/<a href="/wiki/Search/Retrieve_Web_Service" title="Search/Retrieve Web Service">SRW</a> (<i>Search/Retrieve via URL</i>/<i>Search/Retrieve Web service</i>), which drop the Z39.50 communications protocol (replacing it with <a href="/wiki/HTTP" title="HTTP">HTTP</a>) while still attempting to preserve the benefits of the query syntax. SRU is <a href="/wiki/Representational_State_Transfer" class="mw-redirect" title="Representational State Transfer">REST</a>-based, and enables queries to be expressed in <a href="/wiki/Uniform_Resource_Locator" class="mw-redirect" title="Uniform Resource Locator">URL</a> query strings; SRW uses <a href="/wiki/SOAP_(protocol)" class="mw-redirect" title="SOAP (protocol)">SOAP</a>. Both expect search results to be returned as <a href="/wiki/XML" title="XML">XML</a>. </p><p>These projects have a much lower barrier to entry for developers than the original Z39.50 protocol,<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> allowing the relatively small market for library software to benefit from the <a href="/wiki/Web_service" title="Web service">web service</a> tools developed for much larger markets. </p><p>Alternatives include the following.<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> <ul><li>Open Archives Initiative <a href="/wiki/Protocol_for_Metadata_Harvesting" class="mw-redirect" title="Protocol for Metadata Harvesting">Protocol for Metadata Harvesting</a> (OAI-PMH)</li> <li><a href="/wiki/SPARQL" title="SPARQL">SPARQL</a></li></ul> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(3)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="Firewall_information">Firewall information</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Z39.50&action=edit&section=3" title="Edit section: Firewall information" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-3 collapsible-block" id="mf-section-3"> <p>The registered <a href="/wiki/Port_(computer_networking)" title="Port (computer networking)">network port number</a> for Z39.50 is 210. Although the majority of servers use this port, there are dozens of other port numbers used worldwide by Z39.50 (e.g. 2100, 2200, 2210, 2213, 3520, or in one case, ports 2101 and higher for different databases).<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><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> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(4)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="See_also">See also</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Z39.50&action=edit&section=4" title="Edit section: See also" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-4 collapsible-block" id="mf-section-4"> <ul><li><a href="/wiki/Wide_area_information_server" title="Wide area information server">Wide area information server</a> (WAIS)</li> <li><a href="/wiki/Dynix_(software)" title="Dynix (software)">Dynix</a></li> <li><a href="/wiki/Koha_(software)" title="Koha (software)">Koha</a></li> <li><a href="/wiki/OpenURL" title="OpenURL">OpenURL</a></li> <li><a href="/wiki/OpenSearch" title="OpenSearch">OpenSearch</a></li></ul> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(5)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="References">References</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Z39.50&action=edit&section=5" title="Edit section: References" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-5 collapsible-block" id="mf-section-5"> <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 .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://www.loc.gov/standards/sru/specs/cql.html">CQL: the Contextual Query Language: Specifications</a> SRU: Search/Retrieval via URL, Standards, Library of Congress</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"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .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="http://www.dlib.org/dlib/april97/04lynch.html">"The Z39.50 Information Retrieval Standard: Part I: A Strategic View of Its Past, Present and Future"</a>. <i>www.dlib.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2020-01-22</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.dlib.org&rft.atitle=The+Z39.50+Information+Retrieval+Standard%3A+Part+I%3A+A+Strategic+View+of+Its+Past%2C+Present+and+Future&rft_id=http%3A%2F%2Fwww.dlib.org%2Fdlib%2Fapril97%2F04lynch.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AZ39.50" class="Z3988"></span></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"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://pantherfile.uwm.edu/kipp/public/courses/791/791assign-metadataretrieval.html">"Linked Data in Libraries Metadata Retrieval and Harvesting"</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Linked+Data+in+Libraries+Metadata+Retrieval+and+Harvesting&rft_id=https%3A%2F%2Fpantherfile.uwm.edu%2Fkipp%2Fpublic%2Fcourses%2F791%2F791assign-metadataretrieval.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AZ39.50" class="Z3988"></span></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 class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.loc.gov/z3950/agency/wisdom/firewall.html">"Library of Congress Z39.50 Firewall Information"</a>. <i><a href="/wiki/Library_of_Congress" title="Library of Congress">Library of Congress</a></i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Library+of+Congress&rft.atitle=Library+of+Congress+Z39.50+Firewall+Information&rft_id=https%3A%2F%2Fwww.loc.gov%2Fz3950%2Fagency%2Fwisdom%2Ffirewall.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AZ39.50" 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"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml">"IANA Port and Protocol Registry"</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=IANA+Port+and+Protocol+Registry&rft_id=https%3A%2F%2Fwww.iana.org%2Fassignments%2Fservice-names-port-numbers%2Fservice-names-port-numbers.xhtml&rfr_id=info%3Asid%2Fen.wikipedia.org%3AZ39.50" class="Z3988"></span></span> </li> </ol></div></div> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(6)"><span class="indicator mf-icon mf-icon-expand mf-icon--small"></span><h2 id="External_links">External links</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Z39.50&action=edit&section=6" title="Edit section: External links" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet "> <span class="minerva-icon minerva-icon--edit"></span> <span>edit</span> </a> </span> </div><section class="mf-section-6 collapsible-block" id="mf-section-6"> <ul><li><a rel="nofollow" class="external text" href="https://www.loc.gov/z3950/agency/">Z39.50 Maintenance Agency</a></li> <li><a rel="nofollow" class="external text" href="https://www.loc.gov/z3950/agency/Z39-50-2003.pdf">Z39.50 Standard Document (pdf)</a></li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul 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minerva-icon-size-medium minerva-icon--modified-history"></span> <span class="last-modified-bar__text modified-enhancement" data-user-name="Citation bot" data-user-gender="unknown" data-timestamp="1710536846"> <span>Last edited on 15 March 2024, at 21:07</span> </span> <span class="minerva-icon minerva-icon-size-small minerva-icon--expand"></span> </div> </a> <div class="post-content footer-content"> <div id='mw-data-after-content'> <div class="read-more-container"></div> </div> <div id="p-lang"> <h4>Languages</h4> <section> <ul id="p-variants" class="minerva-languages"></ul> <ul class="minerva-languages"><li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%A8%D8%B1%D9%88%D8%AA%D9%88%D9%83%D9%88%D9%84_Z39.50" title="بروتوكول Z39.50 – Arabic" lang="ar" hreflang="ar" data-title="بروتوكول Z39.50" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Z39.50" title="Z39.50 – Catalan" lang="ca" hreflang="ca" data-title="Z39.50" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Z39.50" title="Z39.50 – Czech" lang="cs" hreflang="cs" data-title="Z39.50" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Z39.50" title="Z39.50 – Danish" lang="da" hreflang="da" data-title="Z39.50" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Z39.50" title="Z39.50 – German" lang="de" hreflang="de" data-title="Z39.50" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Z39.50" title="Z39.50 – Spanish" lang="es" hreflang="es" data-title="Z39.50" 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%D8%B1%D9%88%D8%AA%DA%A9%D9%84_%D8%B2%D8%AF%DB%B3%DB%B9%D9%AB%DB%B5%DB%B0" title="پروتکل زد۳۹٫۵۰ – Persian" lang="fa" hreflang="fa" data-title="پروتکل زد۳۹٫۵۰" 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/Z39.50" title="Z39.50 – French" lang="fr" hreflang="fr" data-title="Z39.50" 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/Z39.50" title="Z39.50 – Korean" lang="ko" hreflang="ko" data-title="Z39.50" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Z39.50" title="Z39.50 – Italian" lang="it" hreflang="it" data-title="Z39.50" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/Z39.50" title="Z39.50 – Hebrew" lang="he" hreflang="he" data-title="Z39.50" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Z39.50_protokoll" title="Z39.50 protokoll – Hungarian" lang="hu" hreflang="hu" data-title="Z39.50 protokoll" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/Z39.50" title="Z39.50 – Japanese" lang="ja" hreflang="ja" data-title="Z39.50" 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/Z39.50" title="Z39.50 – Polish" lang="pl" hreflang="pl" data-title="Z39.50" 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/Z39.50" title="Z39.50 – Portuguese" lang="pt" hreflang="pt" data-title="Z39.50" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/Z39.50" title="Z39.50 – Russian" lang="ru" hreflang="ru" data-title="Z39.50" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/Z39.50" title="Z39.50 – Serbian" lang="sr" hreflang="sr" data-title="Z39.50" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/Z39.50" title="Z39.50 – Ukrainian" lang="uk" hreflang="uk" data-title="Z39.50" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li></ul> </section> </div> <div class="minerva-footer-logo"><img src="/static/images/mobile/copyright/wikipedia-wordmark-en.svg" alt="Wikipedia" width="120" height="18" style="width: 7.5em; height: 1.125em;"/> </div> <ul id="footer-info" class="footer-info hlist hlist-separated"> <li id="footer-info-lastmod"> This page was last edited on 15 March 2024, at 21:07<span class="anonymous-show"> (UTC)</span>.</li> <li id="footer-info-copyright">Content is available under <a class="external" rel="nofollow" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">CC BY-SA 4.0</a> unless otherwise noted.</li> </ul> <ul id="footer-places" class="footer-places hlist hlist-separated"> <li 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