Karen Kingston (2016). “Clear Your Clutter with Feng Shui (Revised and Updated): Free Yourself from Physical, Mental, Emotional, and Spiritual Clutter Forever”, p.189, Harmony
"We'll Never Conquer Space". Essay by Arthur C. Clarke first published in "Science Digest" (June 1960); later published in Arthur C. Clarke "Profiles of the Future: An Inquiry into the Limits of the Possible", 1962, in Arthur C. Clarke "Voices from the Sky", 1965, and in Arthur C. Clarke "Greetings, Carbon-Based Bipeds!: Collected Essays, 1934-1998", 1999.