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Yoga Teachers
By an Amazon.com customer
Yoga:  The Iyengar WayYoga: The Iyengar Way by Silva Mehta
Buy new: $16.47 / Used from: $8.68
This was my very first book I ever owned and it is still the one I refer to the most. If you only want one book on your shelf, this book is it.
Yoga Mind, Body & Spirit: A Return to WholenessYoga Mind, Body & Spirit: A Return to Wholeness by Donna Farhi
Buy new: $14.96 / Used from: $9.75
Another book I frequently turn to for inspiration. She does an amazing job of describing the deeper actions in the body for the asana. Lovely!