Here we have two texts that are very important to Sensei Bigelow and to the art of kosho as a whole. The first one is a first edition of Ultimate Kempo by Jeff Driscoll.
Ultimate Kempo is more than a book about technique and style;it's a study of movement, motion and balance that can enhance anyone'sstudy of the martial arts. Its primary focus is not to inflict harm,but to avoid conflict through an understanding of Kosho Ryu's uniquemental discipline and philosophy. If physical confrontation isunavoidable, then practitioners of kempo will learn to manipulate thebalance and the structure of an opponent for optimal results. Withhundreds of photographs and the provided DVD, Ultimate Kempo gives systematic guidance for maximum effectiveness in the striking, throwing and locking arts. 
The second text we have here is not just one book, but many books in one. This text is Hansh Juchnik's text, the collection. This book includes four of Hanshi's hard to find books; The Last Disciple where he talks about the lessons he receved from Mitose, To Fall Seven, To Rise Eight, in which he talks about the interactions he had with Mitose, Kosho Ryu No Kenza, and Strategies and Studies of Kosho Ryu Kempo