The Yoga of Tibet : the Great Exposition of Secret Mantra 2 and 3 / Tsong-Ka-Pa ; introduced by His Holiness Tenzin Gyatso, ... ; translated and edited by Jeffrey Hopkins ; associate editors for Tsong-ka-pa's text : Lati Rinbochay and Denma Lochö Rinbochay ; assistant editor : Elizabeth Napper / London : George Allen & Unwin , 1981