• September and November 2010 issues of “Yoga Journal”; specifically, articles on the history of yoga
• “Light on Yoga” by BKS Iyengar; specifically, “Part One – What is Yoga”
• “First There is a Mountain” by Elizabeth Kadetsky; presents an objective view of BKS written by a journalist who became part of his inner circle; includes many historical references
• “The Bhagavad Gita” by Winthrop Sargeant; this is the truest transliteration from Sanskrit to English; good to use as a reference though no commentary
• Any of several readily available books on the two widely recognized original and authoritative texts on Raja Yoga: the Bhagavad Gita, and the Yoga Sutras of Patanjali. Reading multiple interpretations provides a broader understanding of the material.
• Swamij.com
• Any of several anatomy books written for yoga students, for example, “Anatomy of Hatha Yoga” by H David Coulter, or “The Key Muscles of Hatha Yoga” by Ray Long
• “Hatha Yoga Pradipika” – the version I have was written by Swami Muktibodhananda
• “Light on Pranayama” by BKS Iyengar
• Anything by Thich Nhat Hanh, including the “Miracle of Mindfulness”; while Buddhist, this is good description of what yogis refer to as a clear and correct state of mind