Author: Krishna Chaitanya Velaga
Edited by: Chinmayi S K and Rohini Lakshané
Reviewed by: Rohini Lakshané


A citation (or reference) identifies the source of information. Verifiability, according to Wikipedia's policy, "means that other people using the encyclopedia can check that the information comes from a reliable source". Wikipedia has a policy for the kind of sources that may be cited. Acceptable sources are generally referred to as "reliable sources". Some typical examples of reliable sources include books published by trusted publishers, reputable news sources, and peer-reviewed journals. Blogs, especially those published on free-of-cost platforms such as, and self-published sources are generally not considered acceptable.1

Original research, that is, research that is not yet published in reliable sources is not accepted on Wikipedia. The content you contribute needs to be supported by material previously published in reliable sources of information. The definition of "original research" also includes the scenario in which information from multiple reliable sources is synthesised to imply causality or correlation that is not supported by any reliable source. Such cases are not considered acceptable, because the eventual claim or implication is still new and yet unpublished in reliable sources.

Unreferenced material may be removed from Wikipedia because such material is unverified. In such cases, you may notice that a "citation needed" tag is placed next to the statement that needs a reference to support its veracity.

What is Citation Hunt?

Citation Hunt is a game-like tool, which can be used to find statements on Wikipedia that need inline citations. As of July 2018, the tool is operational for Wikipedia in English and 57 other languages.

The tool finds the articles on English Wikipedia that contain at least one "citation needed" tag. In the articles on Wikipedias in other languages the tool searches for tags equivalent to"citation needed" . The tool then enables the user to find unreferenced statements based on their topic(s) of interest.

The search box in Citation Hunt suggests topics relevant to keywords entered by the user. Based on the topics, Citation Hunt searches the categories on Wikipedias for article(s) with unsourced statements. The best practice for adding references to an article is to insert citations inline, i.e., immediately after the sentence, line, or paragraph supported by the citation. [Reviewer's note: In the context of this learning module, users may search for keywords relevant to the gaps they are trying to address. For example, keywords relevant to addressing the gender gap in content, such as "women scientists" or "women's suffrage".]

Events for academicians or librarians

If you would like to take a more nuanced approach to the issue of lack of citations in articles, Citation Hunt can be used to put together a list of the kind of references that are missing. Using this list, you may organise an activity or event in a library or an educational institution that houses the sources necessary to fill the citation gap and add value to your work. For example, take a look at this report of an event held in Warangal and Guntur in India in 2018. The Citation Hunt tool was used to demonstrate to the participants, who were faculty in the local universities, how they could add references to Wikipedia.

The discussions at such events may be framed to find answers to the following questions:

  1. What kind of reliable sources does the institution offer?
  2. How can these sources be put to the best use to add to the knowledge present on Wikimedia projects?

The outcome of these discussions may pave the path to collaborate further with the institution, depending on the willingness of the institutions and the resources available with them. For example, if a discussant says, "My library has sources that could be digitised", then a GLAM activity with Wikimedia volunteers could be planned at the library. Alternatively, if the library or institution possesses publications, books or documents, then you may want to consider conducting a "1 Librarian 1 Reference" session or a similar activity to improve and add citations.

"1 Librarian 1 Reference", stylised as #1Lib1Ref, is an annual campaign run by The Wikipedia Library to address the lack of citations on various Wikipedias. The campaign is run twice every year. The first iteration runs from 15 January to 5 February, and the second from 15 May to 5 June. It was started to engage librarians around the world to improve citations on Wikipedia. Over the years, the scope of the campaign has been broadened to include the idea of adding citations in any setting. #1Lib1Ref session may also be organised at times other than the campaign period, depending on your convenience. (For case studies of #1Lib1Ref, see:

You may promote the use of Citation Hunt and #1Lib1Ref events in your community to emphasise the importance of citing reliable sources. Wikipedias from some emerging communities do not have the necessary policies for ensuring verifiability of content and notability of the subject matter. As these communities often have limited resources, both in terms of humanpower and information resources, even if such policies exist, their enforcement has generally been weak. In the recent times, several communities have started focusing on quality over quantity of content in Wikipedia articles. To address these issues and to make contributors aware of the importance of inline citations and reliable sources, a campaign such as #1Lib1Ref may be an effective way to push the momentum.

How to use Citation Hunt

Screenshot: Categories on Citation Hunt

This video illustrates how to add a reference to an article on Wikipedia using Citation Hunt: .webm (To watch a video about adding references to Wikipedia articles in general, see:

You can preview a statement from a random article on the topic you select. If you wish to add a citation for that statement, click the "I've got this" button to go the section of the article where the statement is present, and make the edit. If you are not interested in the statement, click the "Next" button, so that another random statement is pulled in.

Use in languages other than English

If you are conducting an event or activity on a non-English Wikipedia, you may set the preferred language accordingly. If you find that the tool is not available for Wikipedia in your language but you wish to use it, follow the instructions here:

Recommended uses

This tool may be used at:

  1. Edit-a-thons and editing campaigns focused on improving references on Wikipedia
  2. #1Lib1Ref sessions

This text has been released under a Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license. Preferred attribution: Krishna Chaitanya Velaga, Community Toolkit for Greater Diversity. Attribution URL:


  1. See Wikipedia: Reliable Sources -- Perennial Sources

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