There is not much literature on polyphase sleep right now. This book is nothing more than the accumulated experience and personal observations (mostly written on paper napkins) of one of the most famous experimenters with polyphase sleep - me. I created the term "Uberman Sleep Schedule" and lived in both modes - both Uberman and regular, and also tried to advise, learned from other people interested in polyphase sleep. In general, all this is YMMV (Your Mileage May Vary - letters, translation - Your mileage may be different, translation in meaning - Everyone has their own path), but this publication is the best information I know. Accept the book as serious advice, but not as a scientifically confirmed fact, which it is not.