APA (7e ed.) Bronvermelding

Ward, P. D. (1992). On Methuselah's trail: Living fossils and the great extinctions. W.H. Freeman.

Chicago (17e ed.) Bronvermelding

Ward, Peter Douglas. On Methuselah's Trail: Living Fossils and the Great Extinctions. New York: W.H. Freeman, 1992.

MLA (9e ed.) Bronvermelding

Ward, Peter Douglas. On Methuselah's Trail: Living Fossils and the Great Extinctions. W.H. Freeman, 1992.