Chogyam Trungpa (2010). “The Collected Works of Chogyam Trungpa: Volume Four: Journey without Goal; The Lion's Roar; The Dawn of Tantra; An Interview with Cho gyam Trungpa”, p.415, Shambhala Publications
Chogyam Trungpa (2010). “The Collected Works of Chogyam Trungpa: Volume Four: Journey without Goal; The Lion's Roar; The Dawn of Tantra; An Interview with Cho gyam Trungpa”, p.423, Shambhala Publications