Butler, R. N., Lewis, M. I., & Sunderland, T. (1991). Aging and mental health: Positive psychosocial and biomedical approaches (Fourth edition.). Macmillan Publishing Company.
Chicago-viite (17. p.)Butler, Robert N., Myrna I. Lewis, ja Trey Sunderland. Aging and Mental Health: Positive Psychosocial and Biomedical Approaches. Fourth edition. New York: Macmillan Publishing Company, 1991.
MLA-viite (9. p.)Butler, Robert N., et al. Aging and Mental Health: Positive Psychosocial and Biomedical Approaches. Fourth edition. Macmillan Publishing Company, 1991.
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