https://en.wikipedia.org/wiki/Wikipedia:User_scripts/List#References_2
Is there a bot somewhere scanning for duplicate urls in refs?
https://en.wikipedia.org/wiki/Category:All_articles_with_duplicate_citations
https://en.wikipedia.org/wiki/Template:Catalog_lookup_link#See_also
https://en.wikipedia.org/wiki/Wikipedia:Village_pump_(technical)#Duplicated_citations