Bennett, Willard E.
McGraw-Hill, 1959
Buku Teks
Topchik, Gary S.
American Management Association, 2007
eBooks
Chrispinus Dimpudus
Fakultas Ekonomi dan Bisnis Universitas Indonesia, 1997
UI - Tesis Membership
Iaconetti, Joan
Macmillan, 1985
Buku Teks
Dwi Wahyuni Prabawanti
Fakultas Psikologi Universitas Indonesia, 2006
UI - Tugas Akhir