Passmore, J. (1972). The perfectibility of man ([1st ed., reprinted.). Duckworth.
Chicago-viite (17. p.)Passmore, John. The Perfectibility of Man. [1st ed., reprinted. London,: Duckworth, 1972.
MLA-viite (8. p.)Passmore, John. The Perfectibility of Man. [1st ed., reprinted. Duckworth, 1972.
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