Nasution, Rika Sahara
Fakultas Ekonomi dan Bisnis Universitas Indonesia, 2012
UI - Tesis Membership
The World Bank, 1996
Buku Teks SO
Milan, Deanne K.
Random House, 1988
Buku Teks
Evans, Desmond W.
Pitman, 1989
Buku Teks SO
Ory, John C.
Sage, 1993
Buku Teks