How reliable is Wikipedia?
Wikipedia articles should be written in a neutral style and should cite appropriate sources. You will see the phrase  where a statement is being made on a Wikipedia page that needs to be backed up by reference to a source.
Citation Hunt is a neat tool that helps to find missing citations on Wikipedia. You can then search for an appropriate source to use to update the article.
How many citations can you fix in 10 minutes?
- Login to Wikipedia
- Make sure you have the Visual Editor enabled
- Click Preferences in the menu at the top right of the screen.
- Select the Editing tab
- In the Editor section, uncheck Temporarily disable the visual editor while it is in beta
- In Editing Mode, choose Show me both editor tabs.
- Go to Citation Hunt
- Find a snippet that needs a citation (you can restrict the search to specific categories – type into the box under the buttons) and click I’ve got this! to open the Wikipedia page
- Do some searching on the web until you find a good quality, reliable source. Remember – no fake news!
- Edit the Wikipedia article and click to insert a reference at the appropriate point in the article, replacing the  text.
- Save the article.
- Go back to Citation Hunt and find another article to fix!
- Introduction to referencing with VisualEditor (Wikipedia)
- 5 min video tutorial explaining Citation Hunt
(By futureatlas.com (originally posted to Flickr as "Citation needed") [CC BY 2.0 (http://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons)