Tarone, Elaine
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Buku Teks
edited for the International Epidemiological Association and the World Health Organization by Basil S. Hetzel
Oxford University Press, 1978
Buku Teks
Baah, Asamoah
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Buku Teks
Grant, James P.
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Buku Teks
1972, The Hague Mouton
Buku Teks