Gaya APA

Physical Geology. (2007). New York: [s.n.].

Gaya Chicago

Physical Geology. . New York: [s.n.], 2007. Text.

Gaya MLA

Physical Geology. . New York: [s.n.], 2007. Text.

Gaya Turabian

Physical Geology. New York: [s.n.], 2007. Print.