Smil, V. (1993). Global Ecology Environmental Change And Social Flexibility Valclav Smill. Routledge.
Chicago-viite (17. p.)Smil, Vacent. Global Ecology Environmental Change And Social Flexibility Valclav Smill. Routledge, 1993.
MLA-viite (8. p.)Smil, Vacent. Global Ecology Environmental Change And Social Flexibility Valclav Smill. Routledge, 1993.
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