Smil, V. (1993). Global ecology: Environmental change and social flexibility. Routledge.
Chicago-viite (17. p.)Smil, Vaclav. Global Ecology: Environmental Change and Social Flexibility. London: Routledge, 1993.
MLA-viite (9. p.)Smil, Vaclav. Global Ecology: Environmental Change and Social Flexibility. Routledge, 1993.
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