|Inaugurated||15 January 2016– 23 January 2016|
|Next event||15 May 2022– 5 June 2022|
#1Lib1Ref (known in some Romance languages as #1Bib1Ref) is a Wikipedia campaign inviting every librarian on Earth to participate in the online encyclopedia project, specifically improving articles by adding citations.
The first #1Lib1Ref campaign coincided with the 15th anniversary of the founding of Wikipedia in January 2016. Based on the premise of One Librarian, One Reference, organizers estimated that if each librarian on the planet spent 15 minutes adding a citation, the combined effort would eliminate English Wikipedia's backlog of 350,000  notices. The inaugural, weeklong event ran from 15–23 January 2016, and employed the hashtag #1lib1ref on various social media platforms.
Results of the first campaign
The inaugural campaign ended with 1,232 revisions on 879 pages, by 327 users in 9 languages, using the hashtag #1lib1ref in the edit summary; these numbers likely underestimate the overall impact, since many participants were observed omitting the hashtag from edit summaries. On Twitter the #1lib1ref hashtag was used in over 1,100 posts by over 630 users.
The campaign has been revived as an annual celebration of Wikipedia's birthday, expanding into a three-week event in subsequent years. The 1Lib1Ref campaign is part of the Wikimedia Foundation's GLAM outreach strategy to involve librarians in the improvement of Wikipedia.
- Rust, Amanda (14 January 2016). "#1Lib1Ref: Imagine a World Where Every Librarian Added One More Reference to Wikipedia". Retrieved 15 January 2016.
- "#1Lib1Ref ACRL TechConnect Blog". ACRL. 15 January 2016. Retrieved 15 January 2016.
- Scheeder, Donna (15 January 2016). "Wikipedia birthday greetings". International Federation of Library Associations and Institutions. Retrieved 15 January 2016.
- "The Wikipedia Library/1Lib1Ref". Wikimedia Foundation. Retrieved 15 January 2016.
- Stinson, Alex (15 January 2016). "#1Lib1Ref: Help Celebrate Wikipedia's Birthday during 15–23 January by Adding a Reference". Retrieved 15 January 2016.
- "1Lib1Ref Lessons - 2016 Outcomes by the numbers". Retrieved 2 January 2019.
- "Springfield, Greene County librarians add to Wikipedia #1Lib1Ref campaign. You can, too". Springfield News-Leader. Retrieved 13 May 2018.
- "1Lib1Ref". Folgerpedia. Folger Shakespeare Library. Retrieved 23 January 2018.
- "Wikipedia's 2018 #1lib1ref Campaign". Idaho Commission for Libraries. Retrieved 2 January 2019.
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