The Wikipedia policy on this is clear: "Do NOT use articles from Wikipedia (whether this English Wikipedia or Wikipedias in other languages) as sources." from: https://en.wikipedia.org/wiki/Wikipedia:Verifiability#Wikipe...

However, this is an issue to be watchful of indeed, as Wikipedia grows ever larger and gets used more and more.

See also http://wikicite.org (storing citations in Wikidata) which could help bring in better citation (quality) tools. Scholia is an interesting project using that citation data: https://scholia.toolforge.org/