APA

Mertens R., . (1960). The world of amphibians and reptiles. New York: McGraw-Hill.

Chicago

Mertens Robert, . 1960. The world of amphibians and reptiles. New York: McGraw-Hill.

Harvard

Mertens R., . (1960). The world of amphibians and reptiles. New York: McGraw-Hill.

MLA

Mertens Robert, . The world of amphibians and reptiles. New York: McGraw-Hill. 1960.