He is best known for his work on the 1960s spy drama The Avengers with Brian Clemens, Fennell also produced (with Clemens) its follow-up, The New Avengers and The Professionals. The New Avengers was made by The Avengers (Film and TV) Enterprises Ltd, and The Professionals was by Mark One Productions. both companies Fennell established with Clemens and composer Laurie Johnson.
- "Albert Fennell".
- McFarlane, Brian, ed. (16 May 2016). "The Encyclopedia of British Film: Fourth edition". Oxford University Press – via Google Books.
- "BFI Screenonline: Clemens, Brian (1931-) Biography".
- "TV Times magazine, page 22, 22nd October, 1977".
- "And Soon the Darkness (1970)".
- "BFI Screenonline: Dr Jekyll and Sister Hyde (1971) Credits".
- "Captain Kronos: Vampire Hunter (1974) - Brian Clemens - Cast and Crew - AllMovie".