I heartily recommend the book 'Ashtanga Yoga' written by David Swenson. This is a must-read for anybody interested in this particular style of yoga, which translates into English as follows: Ashta = Eight, Anga = Limb, Yoga = Union (The Eight Limbs of Yoga). David has been practising yoga since he was 13 years old and has made a life-time study of the Ashtanga series. The book looks at both the primary and intermediate series, and also offers some short forms of the practice, which are particularly useful for when time is restricted. I love the way David has put variations for all the poses. He offers at least three different options for each pose, thus making the Ashtanga series available to all. Having studied yoga with David back in the early 90's, I don’t think this book reflects his sense of humour, which has to be experienced by meeting the man in person. The book does, however, reflect his amazing wisdom of the Ashtanga Series as taught to him by Sri K. Pattabhi