sa dge bka' rnying gi dgongs pa'i spyi babs gcig tu sgrub pa dag snang nyin byed 'od 'bar

by 1970 rin chen tshe ring/ 'ba' gzhung rin chen tshe ring

Description of the ultimate wisdom that descended the essence of Tibetan Buddhist major schools, Sakya, Gelug, Kagyud, and Nyingma.