Overbeek, J. (1970). Comparative thoughts on overpopulation between the two world wars. Drukkerij Princo.
Chicago-viite (17. p.)Overbeek, Johannes. Comparative Thoughts on Overpopulation Between the Two World Wars. Rotterdam: Drukkerij Princo, 1970.
MLA-viite (8. p.)Overbeek, Johannes. Comparative Thoughts on Overpopulation Between the Two World Wars. Drukkerij Princo, 1970.
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