Middleton, N., Weston, S., & Downes, J. (1989). Atlas of environmental issues. Facts on File.
Cita Chicago Style (17a ed.)Middleton, Nick, Steve Weston, y John Downes. Atlas of Environmental Issues. New York: Facts on File, 1989.
Cita MLA (9a ed.)Middleton, Nick, et al. Atlas of Environmental Issues. Facts on File, 1989.
Precaución: Estas citas no son 100% exactas.