I'm looking into expanding on applications of some weapons I own. I have tried applying them to my Bujinkan training and meeting some results, but I'm wondering about looking into any other applications I may have missed. 1. Sai 2. Tonfa 3. Knife (single edge) 4. Nunchaku 5. Kusarigama (and any other weaponry) I get that some of these are in kobudo, so are there any must have reads on the subject?