Solomon, Irving I., author
New American Library , 1968
Buku Teks
Muhammad Umar Gumai, author
2016
UI - Tesis (Membership)
edited by Kenneth D. Lawrence, Ronald K. Klimberg
Emerald, 2016
eBooks
Ramo, Simon
John Wiley & Sons, 1980
Buku Teks
Christensen, C. Roland, author
Harvard University, 1953
Buku Teks