Keyfitz, N. (1968). World population: An analysis of vital data. University of Chicago Pr..
Chicago-čujuhus (17. p.)Keyfitz, Nathan. World Population: An Analysis of Vital Data. Chicago: University of Chicago Pr., 1968.
MLA-čujuhus (9. p.)Keyfitz, Nathan. World Population: An Analysis of Vital Data. University of Chicago Pr., 1968.
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