Cita APA (7th ed.)

Petersen, M. S. (1990). Interpreting earth history: Manual in historical geology (4th ed.). WCBrown.

Cita Chicago (17th ed.)

Petersen, Morris S. Interpreting Earth History: Manual in Historical Geology. 4th ed. Dubuque, IA: WCBrown, 1990.

Cita MLA (9th ed.)

Petersen, Morris S. Interpreting Earth History: Manual in Historical Geology. 4th ed. WCBrown, 1990.