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Shri Singha (Skt. Śrī Siṃha; Tib. ཤྲཱི་སིང་ཧ་, དཔལ་གྱི་སེང་གེ་, Wyl. dpal gyi seng ge) — one of the early masters of the Dzogchen lineage, who was originally from the kingdom of Khotan located in the present day Xinjiang province of China. He was a disciple of Mañjushrimitra and the main teacher of Jñanasutra. He is famous for arranging the teachings of the Pith Instruction Class (mengak dé) into four cycles: outer, inner, secret and innermost secret unsurpassed. His last testament, which he conferred upon Jñanasutra before passing into the rainbow body, is called the Seven Nails.
- Dudjom Rinpoche, The Nyingma School of Tibetan Buddhism, Its Fundamentals and History, trans. and ed. Gyurme Dorje (Boston: Wisdom, 1991), book one, pages 497-501.
- Nyoshul Khenpo, A Marvelous Garland of Rare Gems: Biographies of Masters of Awareness in the Dzogchen Lineage (Junction City: Padma Publications, 2005), pages 39-40.
- Tulku Thondup, Masters of Meditation and Miracles, edited by Harold Talbott (Boston: Shambhala, 1996), pages 62-64.