Carney, Edward
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Buku Teks
Basch, Lester D.
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Buku Teks
Mudd, Norma
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Buku Teks
Burt, Angela
Stanley Thornes, 1995
Buku Referensi
editor, Bud Wileman, Robin Wileman, Bessana C. Sewell
Wileman Publications, 1986
Buku Referensi