Self and other is the Sutrayana method vis-à-vis understanding nonduality. Subject and object is the Outer Tantric method vis-à-vis nonduality. Existence and non-existence is Inner Tantric method vis-à-vis nonduality. Nonduality is the is Dzogchen method vis-à-vis nonduality.”

― Ngak'chang Rinpoche & Khandro Déchen

Tracts of the Sun : An Earth Orbit of Vajrayana Expressions, Ngakpa Chögyam and Khandro Déchen, Aro Books worldwide, 2022
Paperback: ISBN 978-1-898185-28-4 Available from Lulu Publications and other shops worldwide
eBook: ISBN 978-1-898185-32-1 Available from Lulu Publications and other shops worldwide