Baumer, Bettina and Vatsyayan, Kapila. Kalatattvakosa Vol. 1: Pervasive Terms Vyapti (Indira Gandhi National Centre for the Arts). Motilal Banarsidass; Revised edition (1 martie 2001). P. 42.ISBN 8120805844.
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David Gordon White, (1996). The Alchemical Body: Siddha Traditions in Medieval India. Chicago: University of Chicago Press; 18. Quoted online in InfoRefuge "Patanjali’s Yoga Darsana – The Hatha Yoga Tradition." NOTE: Similar identification also made in the Hathayogapradipika (4.50)