Nunley, R. E. (1960). The distribution of population in Costa Rica. National Academy of Sciences, National Research Council.
Chicago-viite (17. p.)Nunley, Robert Edward. The Distribution of Population in Costa Rica. Washington: National Academy of Sciences, National Research Council, 1960.
MLA-viite (9. p.)Nunley, Robert Edward. The Distribution of Population in Costa Rica. National Academy of Sciences, National Research Council, 1960.
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