Παραπομπή σε μορφή APA (7η εκδ.)

Bohlen, S. R. (1998). Geology for a changing world: A science strategy for the Geologic Division of the U.S. Geological Survey, 2000-2010. U.S. G.P.O. Free on application to U.S. Geological Survey, Information Services.

Παραπομπή σε μορφή Chicago (17η εκδ.)

Bohlen, Steven R. Geology for a Changing World: A Science Strategy for the Geologic Division of the U.S. Geological Survey, 2000-2010. Washington, Denver, CO: U.S. G.P.O. Free on application to U.S. Geological Survey, Information Services, 1998.

Παραπομπή σε μορφή MLA (9th εκδ.)

Bohlen, Steven R. Geology for a Changing World: A Science Strategy for the Geologic Division of the U.S. Geological Survey, 2000-2010. U.S. G.P.O. Free on application to U.S. Geological Survey, Information Services, 1998.