Armstrong, Bruce K.
Oxford University Press, 1994
Buku Referensi
MacMahon, Brian
Little, Brown and Company, 1970
Buku Teks SO
Merrill, Ray M.
Jones & Bartlett Learning, 2016
Buku Teks SO
Chattopadhyay, Amit, 1963-
Jones and Bartlett Publishers , 2011
Buku Teks
Weiss, Noel S.
Oxford University Press, 2016
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