edited by Brenna H. Mayer
Lippincott/Willims & Wilkins, 2005
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Hawe, Penelope
MacLennan & Petty, 2000
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Elviera Gamelia
Universitas jenderal soedirman, health sciences faculty, department of public health, 2016
Artikel Jurnal
Fairmont Press , 1997
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Buku Teks SO