ZELINSKY, W. (1970). Geography and a crowding world: A symposium on population pressures upon physical and social resources in the developing lands. O.U.P.
Chicago-viite (17. p.)ZELINSKY, Wilbur. Geography and a Crowding World: A Symposium on Population Pressures upon Physical and Social Resources in the Developing Lands. New York: O.U.P, 1970.
MLA-viite (9. p.)ZELINSKY, Wilbur. Geography and a Crowding World: A Symposium on Population Pressures upon Physical and Social Resources in the Developing Lands. O.U.P, 1970.
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