1. Bharatiya, Yog Sansthan: Asan & Yog Vigyan, 2005.
2. Bernard, Theose Hatha Yoga, London : Rider and Company,1960.
3. Bert, Charles H and Taylor, N.B. The Body London, Chapman and Hall Limited, 1972.
4. Brena, Steven F. Yoga A Medicine New York, The Julian Press, 1972.
5. Charles H Bert and N.B.Taylor, The Body (London Chapmen and Hall Limited, 1972) p. 158.
6. Clarko David H Exercise Physiology USA Englewood Cliff, 1975.
7. Clarko, H Harrison and Clarke, David H Application of Measurement to Physical Education New Jersey, Printica Hall, Inc., 1987