edited by Marius B. Jansen
Princeton University Press , 1965
Buku Teks SO
Dairisena Arsela
Fakultas Psikologi Universitas Indonesia, 2013
UI - Skripsi Membership
Raw, Laurence
British Council , 1994
Buku Teks
editor, Rudolf Schlesinger
Roudledge and Kegan Publishers, 1949
Buku Teks SO
Mina, Eli
[American Management Association;, ], 2002
eBooks