Pringle, Lucy - Crop Circles: The Greatest Mystery of Modern Times, 1999
Ramacharaka, Yogi - Advanced Course in Yogi Philosophy and Oriental Occultism, 1905
Ramacharaka, Yogi - Lessons in Gnani Yoga, 1909
Randazzo, Joseph - The Contactees Manuscript, 1993
Reich M.D., Wilhelm - Contact with Space, 1957
Reich M.D., Wilhelm - Selected Writings, 1960