APA-referens (7:e uppl.)

Sidgwick, H., & Widgery, A. G. (1949). Outlines of the history of ethics: For English readers / by Henry Sidgwick. With an additional chapter by Alban G. Widgery. Macmillan.

Chicago-referens (17:e uppl.)

Sidgwick, Henry, och Alban G. Widgery. Outlines of the History of Ethics: For English Readers / by Henry Sidgwick. With an Additional Chapter by Alban G. Widgery. London: Macmillan, 1949.

MLA-referens (8:e uppl.)

Sidgwick, Henry, och Alban G. Widgery. Outlines of the History of Ethics: For English Readers / by Henry Sidgwick. With an Additional Chapter by Alban G. Widgery. Macmillan, 1949.