Middleton, N., Weston, S., & Downes, J. (1989). Atlas of environmental issues. Facts on File.
Chicago Style (17th ed.) CitationMiddleton, Nick, Steve Weston, i John Downes. Atlas of Environmental Issues. New York: Facts on File, 1989.
Cita MLAMiddleton, Nick, et al. Atlas of Environmental Issues. Facts on File, 1989.
Atenció: Aquestes cites poden no estar 100% correctes.