APA aipamena

Roberts, W. H. (1941). The problem of choice: An introduction to ethics. Boston: Atheneum Press.

Chicago Style aipamena

Roberts, William Hehry. The Problem of Choice: An Introduction to Ethics. Boston: Atheneum Press, 1941.

MLA aipamena

Roberts, William Hehry. The Problem of Choice: An Introduction to Ethics. Boston: Atheneum Press, 1941.

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