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class="page-actions-menu__list-item"> <a role="button" id="ca-edit" href="/w/index.php?title=Query_expansion&action=edit" data-event-name="menu.edit" data-mw="interface" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only cdx-button--weight-quiet edit-page menu__item--page-actions-edit"> <span class="minerva-icon minerva-icon--edit"></span> <span>Edit</span> </a> </li> </ul> </nav>  <div id="mw-content-subtitle"></div> </div> <div id="bodyContent" class="content"> <div id="mw-content-text" 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"> <p><b>Query expansion</b> (<b>QE</b>) is the process of reformulating a given query to improve retrieval performance in <a href="/wiki/Information_retrieval" title="Information retrieval">information retrieval</a> operations, particularly in the context of <a href="/wiki/Query_understanding" title="Query understanding">query understanding</a>.<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> In the context of <a href="/wiki/Search_engine" title="Search engine">search engines</a>, query expansion involves evaluating a user's input (what words were typed into the search query area, and sometimes other types of <a href="/wiki/Data" title="Data">data</a>) and expanding the search query to match additional documents. Query expansion involves techniques such as: </p> <ul><li>Finding <a href="/wiki/Synonym" title="Synonym">synonyms</a> of words, and searching for the synonyms as well</li> <li>Finding semantically related words (e.g. <a href="/wiki/Antonym" class="mw-redirect" title="Antonym">antonyms</a>, <a href="/wiki/Meronym" class="mw-redirect" title="Meronym">meronyms</a>, <a href="/wiki/Hyponym" class="mw-redirect" title="Hyponym">hyponyms</a>, <a href="/wiki/Hypernym" class="mw-redirect" title="Hypernym">hypernyms</a>)</li> <li>Finding all the various <a href="/wiki/Morphology_(linguistics)" title="Morphology (linguistics)">morphological</a> forms of words by <a href="/wiki/Stemming" title="Stemming">stemming</a> each word in the <a href="/wiki/Web_search_query" class="mw-redirect" title="Web search query">search query</a></li> <li>Fixing <a href="/wiki/Typographical_error" title="Typographical error">spelling errors</a> and automatically searching for the corrected form or suggesting it in the results</li> <li>Re-weighting the terms in the original query</li></ul> <p>Query expansion is a methodology studied in the field of <a href="/wiki/Computer_science" title="Computer science">computer science</a>, particularly within the realm of <a href="/wiki/Natural_language_processing" title="Natural language processing">natural language processing</a> and <a href="/wiki/Information_retrieval" title="Information retrieval">information retrieval</a>. </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="#Precision_and_recall_trade-offs"><span class="tocnumber">1</span> <span class="toctext">Precision and recall trade-offs</span></a></li> <li class="toclevel-1 tocsection-2"><a href="#Query_expansion_methods"><span class="tocnumber">2</span> <span class="toctext">Query expansion methods</span></a></li> <li class="toclevel-1 tocsection-3"><a href="#See_also"><span class="tocnumber">3</span> <span class="toctext">See also</span></a></li> <li class="toclevel-1 tocsection-4"><a href="#Software_libraries"><span class="tocnumber">4</span> <span class="toctext">Software libraries</span></a></li> <li class="toclevel-1 tocsection-5"><a href="#References"><span class="tocnumber">5</span> <span class="toctext">References</span></a> <ul> <li class="toclevel-2 tocsection-6"><a href="#Citations"><span class="tocnumber">5.1</span> <span class="toctext">Citations</span></a></li> <li class="toclevel-2 tocsection-7"><a href="#Sources"><span class="tocnumber">5.2</span> <span class="toctext">Sources</span></a></li> </ul> </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="Precision_and_recall_trade-offs">Precision and recall trade-offs</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Query_expansion&action=edit&section=1" title="Edit section: Precision and recall trade-offs" 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>Search engines invoke query expansion to increase the quality of user search results. It is assumed that users do not always formulate search queries using the best terms. Best in this case may be because the database does not contain the user entered terms. </p><p>By <a href="/wiki/Stemming" title="Stemming">stemming</a> a user-entered term, more documents are matched, as the alternate word forms for a user entered term are matched as well, increasing the total <a href="/wiki/Recall_(information_retrieval)" class="mw-redirect" title="Recall (information retrieval)">recall</a>. This comes at the expense of reducing the <a href="/wiki/Precision_(information_retrieval)" class="mw-redirect" title="Precision (information retrieval)">precision</a>. By expanding a search query to search for the synonyms of a user entered term, the recall is also increased at the expense of precision. This is due to the nature of the equation of how precision is calculated, in that a larger recall implicitly causes a decrease in precision, given that factors of recall are part of the denominator. It is also inferred that a larger recall negatively impacts overall search result quality, given that many users do not want more results to comb through, regardless of the precision. </p><p>The goal of query expansion in this regard is by increasing recall, precision can potentially increase (rather than decrease as mathematically equated), by including in the result set pages which are more relevant (of higher quality), or at least equally relevant. Pages which would not be included in the result set, which have the potential to be more relevant to the user's desired query, are included, and without query expansion would not have, regardless of <a href="/wiki/Relevance_(information_retrieval)" title="Relevance (information retrieval)">relevance</a>. At the same time, many of the current commercial search engines use word frequency (<a href="/wiki/Tf-idf" class="mw-redirect" title="Tf-idf">tf-idf</a>) to assist in ranking.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (October 2016)">citation needed</span></a></i>]</sup> By ranking the occurrences of both the user entered words and synonyms and alternate morphological forms, documents with a higher density (high frequency and close proximity) tend to migrate higher up in the search results, leading to a higher quality of the search results near the top of the results, despite the larger recall. </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="Query_expansion_methods">Query expansion methods</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Query_expansion&action=edit&section=2" title="Edit section: Query expansion methods" 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>Automatic methods for query expansion were proposed in 1960 by Maron and Kuhns.<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> Modern query expansion methods either imply document collection analysis (global or local)<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> or are dictionary- or <a href="/wiki/Ontology_(information_science)" title="Ontology (information science)">ontology</a>-based.<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> The global analysis of the document collection is applied for searching for relations between terms. The local analysis refers to the <a href="/wiki/Relevance_feedback" title="Relevance feedback">relevance feedback</a> introduced by Rocchio.<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> Rocchio proposed to judge manually some of the retrieved documents and use this feedback information to expand the query. Since collecting users' judgment can be challenging, only the first top retrieved documents are considered as relevant. This is the so called <a href="/wiki/Pseudo-relevance_feedback" class="mw-redirect" title="Pseudo-relevance feedback">pseudo-relevance feedback</a> (PRF).<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Pseudo-relevance feedback is efficient in average but can damage results for some queries,<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> especially difficult ones since the top retrieved documents are probably non-relevant. Pseudo-relevant documents are used to find expansion candidate terms that co-occur with many query terms.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> This idea was further developed within the relevance <a href="/wiki/Language_model" title="Language model">language model</a> formalism in positional relevance<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> and proximity relevance models<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> which consider the distance to query terms in the pseudo-relevant documents. Another direction in query expansion is the representation of index and query terms in a vector space which can be used to find related terms at query time, using semantic vectors or <a href="/wiki/Word_embedding" title="Word embedding">word embeddings</a>.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> </p><p>More generally, query expansion, with its counterpart <a href="/w/index.php?title=Document_expansion&action=edit&redlink=1" class="new" title="Document expansion (page does not exist)">document expansion</a>, are today implemented in the form of <a href="/w/index.php?title=Vector_databases&action=edit&redlink=1" class="new" title="Vector databases (page does not exist)">vector databases</a>, using various encoding schemes based on <a href="/wiki/Deep_learning" title="Deep learning">deep learning</a>.<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> </p> </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="See_also">See also</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Query_expansion&action=edit&section=3" 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-3 collapsible-block" id="mf-section-3"> <ul><li><a href="/wiki/Document_retrieval" title="Document retrieval">Document retrieval</a></li> <li><a href="/wiki/Information_retrieval" title="Information retrieval">Information retrieval</a></li> <li><a href="/wiki/Linguistics" title="Linguistics">Linguistics</a></li> <li><a href="/wiki/Morphology_(linguistics)" title="Morphology (linguistics)">Morphology (linguistics)</a></li> <li><a href="/wiki/Natural_language_processing" title="Natural language processing">Natural language processing</a></li> <li><a href="/wiki/Search_engine" title="Search engine">Search engine</a></li> <li><a href="/wiki/Search_engine_indexing" title="Search engine indexing">Search engine indexing</a></li> <li><a href="/wiki/Stemming" title="Stemming">Stemming</a></li></ul> </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="Software_libraries">Software libraries</h2><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Query_expansion&action=edit&section=4" title="Edit section: Software libraries" 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 rel="nofollow" class="external text" href="http://qtanalyzer.codeplex.com/">QueryTermAnalyzer</a> open-source, C#. Machine learning based query term weight and synonym analyzer for query expansion.</li> <li><a rel="nofollow" class="external text" href="http://lucene-qe.sourceforge.net/">LucQE</a> - open-source, Java. Provides a framework along with several implementations that allow to perform query expansion with the use of Apache <a href="/wiki/Lucene" class="mw-redirect" title="Lucene">Lucene</a>.</li> <li><a href="/wiki/Xapian" title="Xapian">Xapian</a> is an open-source search library which includes support for query expansion</li> <li><a rel="nofollow" class="external text" href="https://github.com/hosseinfani/ReQue/">ReQue</a> open-source, Python. A configurable software framework and a collection of gold standard datasets for training and evaluating supervised query expansion methods.<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup></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=Query_expansion&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"> <div class="mw-heading mw-heading3"><h3 id="Citations">Citations</h3><span class="mw-editsection"> <a role="button" href="/w/index.php?title=Query_expansion&action=edit&section=6" title="Edit section: Citations" 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> <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 mw-references-columns"><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"><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 id="CITEREFVectomovaWang,_Ying2006" class="citation journal cs1">Vectomova, Olga; Wang, Ying (2006). 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Robinson, The THISL broadcast news retrieval system. In <i>Proc. ESCA ETRW Workshop Accessing Information in Spoken Audio</i>, (Cambridge), pp. 14–19, 1999. Section on <a rel="nofollow" class="external text" href="https://web.archive.org/web/20070328204357/http://homepages.inf.ed.ac.uk/srenals/pubs/1999/esca99-thisl/node6.html">Query Expansion</a> - Concise, mathematical overview.</li> <li>R. Navigli, P. Velardi. <a rel="nofollow" class="external text" href="http://www.dcs.shef.ac.uk/~fabio/ATEM03/navigli-ecml03-atem.pdf">An Analysis of Ontology-based Query Expansion Strategies</a>. <i>Proc. of Workshop on Adaptive Text Extraction and Mining (ATEM 2003)</i>, in the <i>14th European Conference on Machine Learning (ECML 2003)</i>, Cavtat-Dubrovnik, Croatia, September 22-26th, 2003, pp. 42–49 - An analysis of query expansion methods relying on WordNet as the reference ontology.</li> <li>Y. Qiu and H.P. Frei. <a rel="nofollow" class="external text" href="http://citeseer.ist.psu.edu/qiu93concept.html">Concept Based Query Expansion</a>. In <i>Proceedings of SIGIR-93, 16th ACM International Conference on Research and Development in Information Retrieval</i>, Pittsburgh, SIGIR Forum, ACM Press, June 1993 - Academic document on a specific method of query expansion</li> <li>Efthimis N. Efthimiadis. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20061019102218/http://faculty.washington.edu/efthimis/pubs/Pubs/qe-arist/QE-arist.html">Query Expansion</a>. In: Martha E. Williams (ed.), <i>Annual Review of Information Systems and Technology (ARIST)</i>, v31, pp 121–187, 1996 - An introduction for less-technical viewers.</li></ul>    </section></div> <noscript><img src="https://login.m.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1&mobile=1" 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=Query_expansion&oldid=1244806152">https://en.wikipedia.org/w/index.php?title=Query_expansion&oldid=1244806152</a>"</div></div> </div> <div class="post-content" id="page-secondary-actions"> </div> </main> <footer class="mw-footer minerva-footer" role="contentinfo"> <a class="last-modified-bar" href="/w/index.php?title=Query_expansion&action=history"> <div class="post-content last-modified-bar__content"> <span class="minerva-icon minerva-icon-size-medium minerva-icon--modified-history"></span> <span class="last-modified-bar__text modified-enhancement" data-user-name="Horcrux" data-user-gender="male" data-timestamp="1725871907"> <span>Last edited on 9 September 2024, at 08:51</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%AA%D9%88%D8%B3%D9%8A%D8%B9_%D8%A7%D9%84%D8%A7%D8%B3%D8%AA%D8%B9%D9%84%D8%A7%D9%85" title="توسيع الاستعلام – Arabic" lang="ar" hreflang="ar" data-title="توسيع الاستعلام" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Expansi%C3%B3n_de_consultas" title="Expansión de consultas – Spanish" lang="es" hreflang="es" data-title="Expansión de consultas" 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/%DA%AF%D8%B3%D8%AA%D8%B1%D8%B4_%D9%BE%D8%B1%D8%B3%D8%B4" title="گسترش پرسش – Persian" lang="fa" hreflang="fa" data-title="گسترش پرسش" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E6%93%B4%E5%B1%95%E6%9F%A5%E8%A9%A2" title="擴展查詢 – Chinese" lang="zh" hreflang="zh" data-title="擴展查詢" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</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; 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