Summary

• All article content must be verifiable, that is, possible to support with a reliable, published source.
• All quotations, any material whose verifiability has been challenged or is likely to be challenged, and contentious material, whether negative, positive, or neutral, about living persons, must include an inline citation.
• Inline citations are added between <ref>...</ref> tags, after the facts they support.
• A {{Reflist}} template should be added at the end of the article, in a "References" section, for the inline citations to display properly.
• The RefToolbar can be used to make adding citations easier, by clicking "Cite" in the toolbar at the top of the edit window.
• Wikipedia articles require citations to reliable, published sources, with a reputation for fact-checking and accuracy.

Detailed information

• Wikipedia:Verifiability
• Wikipedia:Citing sources
• Wikipedia:Identifying reliable sources
• Wikipedia:References dos and don'ts
• Help:Citations quick reference
• Help:References and page numbers

Put what you learned into practice

There are currently over 518,054 articles that have statements that need citations. The Citation Hunt tool makes referencing those statements easier by suggesting random articles which you can work on. Practice your new skills by helping us solve a "Citation needed" issue:

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