Super Pose Dance & Gymnastics Photo Reference Book
This book, like all the books in this category are full of amazing photos and may contain nudity. These Japanese import books are excellent if you don't have time to attend life drawing classes.
When you just want to draw and not have to think too hard on what to draw. Or when you want to draw anatomy without getting sucked up by the time vortex that is the internet infinity pool ( you know it - you look up a photo to draw and the next thing you know, 6 hours have passed and you got nothing done but clicking on links and getting totally off topic.) Having a book like this in your library really works if you want to get drawing done!