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Buku Teks SO
Golant, Stephen M.
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Buku Teks SO
Tri Budi Wahyuni Rahardjo
UI-Press, 2001
UI - Pidato
Cox, Harold
Prentice-Hall, 1984
Buku Teks SO
International Association of Gerontology; edited by Clark Tibbitts and Wilma Donahue
Columbia University Press, 1962
Buku Teks SO