Bird, J. H. (1989). The changing worlds of geography: A critical guide to concepts and methods. Clarendon Press.
Chicago-viite (17. p.)Bird, James Harold. The Changing Worlds of Geography: A Critical Guide to Concepts and Methods. Oxford: Clarendon Press, 1989.
MLA-viite (9. p.)Bird, James Harold. The Changing Worlds of Geography: A Critical Guide to Concepts and Methods. Clarendon Press, 1989.
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