Stone, Geoffrey R.
Little, Brown and Company, 1991
Buku Teks SO
Wade, E.C.S. [Emlyn Capel Stewart]
Longman, Green, 1951
Buku Teks
Wade, E.C.S. [Emlyn Capel Stewart]
[Publisher not identified], [Date of publication not identified]
Buku Teks
Nowak, John E.
Thomson/West, 2010
Buku Teks SO
Wollstonecraft, Mary
David Campbell Publishers, 1992
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