Kvaerne, Per (1975). "On the Concept of Sahaja in Indian Buddhist Tantric Literature". (NB: article first published in Temenos XI (1975): pp.88-135). Cited in: Williams, Jane (2005). Buddhism: Critical Concepts in Religious Studies, Volume 6. Routledge. (ISBN 0-415-33226-5), (ISBN 978-0-415-33226-2). Source: [2] (alirita la 16an de Aprilo, 2010)