Porterfield, J. D., & St. Pierre, R. W. (1992). Healthful aging. Dushkin Pub. Group.
Chicago Style (17. basım) AtıfPorterfield, James D., ve Richard W. St. Pierre. Healthful Aging. Guilford, CT: Dushkin Pub. Group, 1992.
MLA (9th ed.) AtıfPorterfield, James D., ve Richard W. St. Pierre. Healthful Aging. Dushkin Pub. Group, 1992.
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