ref(s)
Nik Douglas -- SPIRITUAL SEX: Secrets of Tantra From the Ice Age to the New Millennium (amazon)
Georg Feuerstein -- Holy Madness: The Shock Tactics and Radical Teachings of Crazy-Wise Adepts, Holy Fools and Rascal Gurus (amazon)
Omar V. Garrison -- Tantra: Yoga of Sex (amazon)
Howard John Zitko -- New Age Tantra Yoga: The Cybernetics of Sex and Love (amazon)