Źródła - John Cooper:
„The Gameshow Serial Killer: Police Tapes” (2018)
https://www.bbc.com/news/uk-wales-south-west-wales-13409516
https://www.walesonline.co.uk/news/wales-news/pembrokeshire-murders-background-john-cooper-1835442
https://kultura.onet.pl/film/wiadomosci/john-cooper-byl-nieuchwytnym-morderca-wpadl-po-wystepie-w-teleturnieju/zj9wes8
https://www.mirror.co.uk/news/uk-news/john-cooper-was-turned-into-a-serial-killer-131047
https://www.crimeandinvestigation.co.uk/article/john-william-cooper-the-bullseye-murderer
https://www.theguardian.com/uk/2011/may/26/john-cooper-murders-finally-solved
https://www.personsunknown.net/p/the-pembrokeshire-murders-part-1
https://www.personsunknown.net/p/bullseye-killer-part-2