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McGraw-Hill, 1983
Buku Teks
Allen, Peter, author
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Buku Teks
Ahmad Hargi Septiawan, author
Universitas Indonesia, 2013
UI - Skripsi (Membership)
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South-Western Publishing, 1959
Buku Teks
Allen, Robert Y., author
McGraw-Hill, 1984
Buku Teks