Gita : Ch-4. Sl-29.
Srimad Bhagavad-Gita : Chapter-4. ( Jnana-karma-sanyasa-yogam ) Slokam-29. ( And there are even others who are inclined to the process of breath restraint to remain in trance, and they practice stopping the movement of the outgoing breath into the incoming, and incoming breath into the outgoing, and thus at last remain in trance, stopping all breathing. Some of them, curtailing the eating process, offer the outgoing breath into itself, as a sacrifice. ) Apane juhvati pranam pranepanam tathapare, prnapanagati ruddhva pranayamaparayanah. pranayama-parayanah = iterested in pranayamam; apare = some others; prnapana-gati = regulation of the breathing; ruddhva = having controled; pranam apane = the air going outward taken again inward; tatha apanam prane = ...