APA

Kerr J. G., . (1968). A naturalist in the Gran Chaco. New York: Greenwood Press.

Chicago

Kerr John Graham, . 1968. A naturalist in the Gran Chaco. New York: Greenwood Press.

Harvard

Kerr J. G., . (1968). A naturalist in the Gran Chaco. New York: Greenwood Press.

MLA

Kerr John Graham, . A naturalist in the Gran Chaco. New York: Greenwood Press. 1968.