^Pace, Eric (30 September 1997). "Dr. Karl F. Koopman, 77, An Authority on Bats, Is Dead". The New York Times.
^Beolens B, Watkins M, Grayson M. (2011). The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 296 pp.
ISBN978-1-4214-0135-5. ("Koopman", p. 145).