Chen, C.S.
Hoover Institute Press , 1969
Buku Teks
Lethbridge, Henry J.
Dragonfly Books, 1963
Buku Teks
Milivojevic, Dragoljub
Information Service, 1962
Buku Teks
Strong, Anna Louise, author
New World Press, 1959.
Buku Teks
Willimott, Andy, author
Oxford University Press, 2017
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