Keegan, John, author
Gale Research, 1983
Buku Teks
Simatupang, T.B. (Tahi Bonar), 1920-, author
[publisher not identified], [date of publication not identified]
Buku Teks
Amarulla Octavian, author
UI Press, 2012
Buku Teks
Nelson, Daniel J.
Westview Press, 1987
Buku Teks
Simon, Jeffrey
Westview Press, 1985
Buku Teks