The Nyingma are noted for their separate canon, consisting of terma literature and the Compendium of Old Tantras (rnying.maʾi.rgyud.ʾ-bum). While the Tibetan Book of the Dead is the best known, the most important Nyingma text is the Heart-Drop (snying.thig); a terma text discovered in the 12th cent. by Zhangtön and commentated upon by Longchenpa, it contains teachings on Dzogchen (rdzogs.chen; ‘Great Perfection’), the primary Nyingma system of meditation.
The Nyingma has produced several great scholars, such as Longchenpa (1308–63) and Mipham (d. 1912), who was influential in the 19th-cent. Rimé movement. A recent supreme head of the order, Dujom Rinpoche (1904–87) was considered an incarnation of Dujom Lingpa.
"Nyingma." The Concise Oxford Dictionary of World Religions. . Encyclopedia.com. (May 27, 2018). http://www.encyclopedia.com/religion/dictionaries-thesauruses-pictures-and-press-releases/nyingma
"Nyingma." The Concise Oxford Dictionary of World Religions. . Retrieved May 27, 2018 from Encyclopedia.com: http://www.encyclopedia.com/religion/dictionaries-thesauruses-pictures-and-press-releases/nyingma