Cita APA (7a ed.)

CALLENBACH; ERNEST. (2004). ECOLOGY - A POCKET GUIDE (REPRINT.). UNIVERSITIES PRESS.

Cita Chicago Style (17a ed.)

CALLENBACH; ERNEST. ECOLOGY - A POCKET GUIDE. REPRINT. HYDERABAD: UNIVERSITIES PRESS, 2004.

Cita MLA (9a ed.)

CALLENBACH; ERNEST. ECOLOGY - A POCKET GUIDE. REPRINT. UNIVERSITIES PRESS, 2004.

Precaución: Estas citas no son 100% exactas.