Roque, C. R. (1990). Earth, water, air, fire: Essays on environmentalism. Kalikasan press.
Cita Chicago Style (17a ed.)Roque, Celso R. Earth, Water, Air, Fire: Essays on Environmentalism. Manila: Kalikasan press, 1990.
Cita MLA (9a ed.)Roque, Celso R. Earth, Water, Air, Fire: Essays on Environmentalism. Kalikasan press, 1990.
Precaución: Estas citas no son 100% exactas.