One of yoga's most important and influential works, this classicforms a keystone of Indian philosophical and religious thought. The eight-step path to Raja Yoga consists of restraint, observances, posture, breath control, sublimation, attention, concentration, and meditation. This volume contains complete sutras, along with a commentary by Veda-Vyasa and explanations by Vachaspati-Miçra. Unabridged republication of The Yoga-System of Patañjali, or the Ancient Hindu Doctrine of Concentration of Mind, The Harvard University Press, Cambridge, Massachusetts, 1927.
Here's a sample of other books in this Dover category
Yoga as Philosophy and Religion by Surendranath Dasgupta Practical guide promotes Rajayoga and compares its essential features with other yoga systems. First parts deals with yoga metaphysics. Second part expounds yoga ethics and practice.
Yoga: Its Scientific Basis by Kovoor T. Behanan Clearly explains and evaluates fundamental concepts of Hindu thought; development of Hindu religious philosophy; detailed descriptions of the psychology and psychoanalysis of yoga, its postures and varieties of breathing, much more.
The Serpent Power: The Secrets of Tantric and Shaktic Yoga by Arthur Avalon Considered the prime document for study and application of Kundalini yoga, this work probes the philosophical and mythological nature of Kundalini, the esoteric anatomy associated with it, and much more.