GREENWOOD, N., & EDWARDS, J. (1979). Human environments and natural systems. -- 2nd ed. Duxbury Press.
Chicago-viite (17. p.)GREENWOOD, N.H, ja J.M.B EDWARDS. Human Environments and Natural Systems. -- 2nd Ed. North Scituate: Duxbury Press, 1979.
MLA-viite (9. p.)GREENWOOD, N.H, ja J.M.B EDWARDS. Human Environments and Natural Systems. -- 2nd Ed. Duxbury Press, 1979.
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