Singer, M. G. (1980). Is ethics a science? Ought it to be? Zygon, 15(1), 29-42.
Cita Chicago Style (17a ed.)Singer, Marcus George. "Is Ethics a Science? Ought It to Be?" Zygon 15, no. 1 (1980): 29-42.
Cita MLA (8a ed.)Singer, Marcus George. "Is Ethics a Science? Ought It to Be?" Zygon, vol. 15, no. 1, 1980, pp. 29-42.
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