Hays, H.R.
Alfred A. Knofpf, 1958
Buku Teks
Plamenatz, John
Longman Press, 1992
Buku Teks
Plamenatz, John
Longmen Press, 1993
Buku Teks
edited by Charles Leslie
Vintage Books, 1960
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Yunarti, Nurainas, Yulkardi, Fitria Ramona
[Publisher not identified], 2014
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