- Abandomoviez.net (Spanish)
- BCult - Dossier (French)
- DBCult Film Institute - Biography
- DBCult Film Institute - Book
- DBCult Film Institute - Dossier (French)
- Feature on Castle, King of the Movie Gimmicks.
- Find A Grave
- Horror-wood.com - "The William Castle Story"
- Message board (German)
- Paste - 15 Greatest B-Movie Directors [Jim Vorel] (July 2014)
- Tales of Terror - profile [Steve Hutchison]
- The Terror Trap
- Virtual History - Literature
- film-zeit.de - Biography (German)
- reelingback.com [Michael Walsh]