Balisong Manual (June 1, 1984)
Jeff Imada, one of the most respected balisong practitioners in the world, presents the definitive work on the balisong knife.
Everything you always wanted to know about the balisong is featured in this book, with concise text and hundreds of detailed photos showing: carrying, drawing and flipping manipulation techniques; self-defense techniques; the knife and the law; knife-fighting philosophy; care and maintenance; and striking areas.
Available original print $75
Jeff Imada is THE source for butterfly knife technqiues. It's got a great assortment of excercises, openings, closings, and everything else you need to become proficient at the balisong.
Although learning this kind of material is difficult from a printed page (better to have video) this book does a good job in getting it's point across. It's a great reference tool.