Essence of Pranayama by Srikrishna
This book has been written mainly as a friendly companion, an adjuvant to a training in Pranayama under personal supervision of a teacher. It has been written with a view to give that student a correct and the comprehensive information on all the different aspects of Pranayama. It would help in making the actual practice of Pranamaya more effective as the student will be able to discern between the essential and the optional parts of the different techniques of Pranayama. It would also help the student to keep the spiritual perspective in the forefront while undertaking the practice of Pranayama.