World Resources Institute, United Nations Environment Programme, & United Nations Development Programme. (1990). World resources. Oxford University Press.
Citazione stile Chigago Style (17a edizione)World Resources Institute, United Nations Environment Programme, e United Nations Development Programme. World Resources. New York: Oxford University Press, 1990.
Citatione MLA (8a ed.)World Resources Institute, et al. World Resources. Oxford University Press, 1990.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.