Author: Stryk, Lucien
Publisher:Doubleday & Company, New York
Copyright:1968
Author: Brahmachari, Dhirendra
Publisher:Asia Publishing House, Bombay
Copyright:1970
Author: Rele, V. G.
Publisher:D B Taraporevala sons and co., Bombay
Copyright:1944
Author: Sivananda, Swami
Publisher:D B Taraporevala sons and co., Bombay
Copyright:1944