Roberts, Terence
Chronological Checklist
- Report on the Status Quo (New York: Merlin Press, Inc, 1955)
- Abominable Snowmen: Legend Come to Life – The Story of Sub-Humans on Five Continents from the Early Ice Age Until Today (Philadelphia, Pennsylvania: Chilton Book Company, 1961) as Ivan T Sanderson
- Uninvited Visitors: A Biologist Looks at UFOs (New York: Cowles Books, 1967) as Ivan T Sanderson
- "Things": Monsters, Mysteries, Marvels, Uncanny, Strange but True (New York: Pyramid Books, 1967) as Ivan T Sanderson
- Abominable Snowmen: Legend Come to Life – The Story of Sub-Humans on Five Continents from the Early Ice Age Till Today (New York: Pyramid Books, 1968) as Ivan T Sanderson
- More "Things" (New York: Pyramid Books, 1969) as Ivan T Sanderson
- Invisible Residents: A Disquisition Upon Certain Matters Maritime, and the Possibility of Intelligent Life Under the Waters of This Earth (New York: World Publishing Company, 1970) as Ivan T Sanderson
- Investigating the Unexplained: Disquieting Mysteries of the Natural World (Englewood Cliffs, New Jersey: Prentice-Hall, Inc, 1972) as Ivan T Sanderson