Books like Yoga by David Frawley

A curated anthology of Aleister Crowley's key writings, annotated by Scott Michaelsen, that brings the mystic’s complex theories of Qabalah, magic, yoga, and occult practice into clearer focus for both newcomers and seasoned students.

In Iyengar's classic [Light on Yoga][1], Iyengar described in great detail the classic poses of Yoga. In this book, Iyengar moves beyond the physical aspects of Yoga to discuss the mental and spiritual aspects. [1]: http://openlibrary.org/works/OL3018499W/Light_on_yoga

"A History of Modern Yoga traces the roots of Modern Yoga back to the spread of western esoteric ideas in 18th century Bengal's intellectual circles. In due course Raja Yoga, published by Vivekananda in 1896, became the seminal text of Modern Yoga largely because, the author shows, it reconfigured the Yoga Sutras of Patanjali along the lines of a then emerging New Age occultistic style of secularised and individualistically oriented religiosity. With regard to 20th century developments, this book proposes a four-fold typology of Modern Yoga comprising Modern Psychosomatic, Modern Meditational, Modern Postural and Modern Denominational forms. Iyengar Yoga, one of the most influential schools of Modern Postural Yoga, is then analyzed in the light of this framework, while the conclusion shows how a typical Modern Postural Yoga session may be interpreted to reveal the forms and contents of a healing ritual of secular religion."--Bloomsbury Publishing.

A critical edition of the Bhagavad Gita that removes 109 interpolations to restore its original spiritual and philosophical teachings—offering a clearer view of Hindu thought on duty, karma, and liberation as set against the Mahabharata’s war.