APA-viite (7. p.)
Achenbaum, W. A. (2013). Robert N. Butler, MD: Visionary of healthy aging. Columbia University Press.
Chicago-viite (17. p.)
Achenbaum, W. Andrew. Robert N. Butler, MD: Visionary of Healthy Aging. New York: Columbia University Press, 2013.
MLA-viite (9. p.)
Achenbaum, W. Andrew. Robert N. Butler, MD: Visionary of Healthy Aging. Columbia University Press, 2013.
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