APA (7e ed.) Bronvermelding

Não informado. (2014). Geological Survey Professional Paper. U.S. Geological Survey Professional Paper.

Chicago (17e ed.) Bronvermelding

Não informado. Geological Survey Professional Paper. Washington: U.S. Geological Survey Professional Paper, 2014.

MLA (8e ed.) Bronvermelding

Não informado. Geological Survey Professional Paper. U.S. Geological Survey Professional Paper, 2014.

Let op: Deze citaties zijn niet altijd 100% accuraat.