4-time Boomerang Team World Champion and 13-time Event World Record Holder John Flynn presents a comprehensive overview on boomerangs on the Woodstock Community Television channel.
The talk was released in conjunction with his book, 50 Important Boomerangs: Pictures and Essays Celebrating the Modern Boomerang’s Evolution.
A selection of open-source/digitised works on this topic (via Internet Archive). The Internet Archive might require you to sign-up for a free account and digitally 'borrow' the book to view.
1974 - Boomerangs: Hot to Make and Throw Them by Bernard S. Mason
https://archive.org/details/boomerangs-make-throw
(If you are in Singapore, I do have a physical copy for loan/viewing.)
1977 - Many Happy Returns by Benjamin Ruhe
https://archive.org/details/manyhappyreturns0000ruhe
(If you are in Singapore, I do have a physical copy for loan/viewing.)
1997 - Boomerang: Behind an Australian Icon by Philip Jones
https://archive.org/details/boomerangbehinda0000jone
1998 - The Boomerang Information Book by S.G. King
https://archive.org/details/boomeranginforma00king