Hadari Nawawi, author
Gadjah Mada University Press, 2006
Buku Teks
J. Winardi, author
RajaGrafindo Persada, 2002
Buku Teks
Riza Umary, author
Fakultas Ekonomi dan Bisnis Universitas Indonesia, 2008
UI - Tesis (Open)
Dody Effendi
Abdi Tandur, 1999
Buku Teks
Walters, Jamie S, author
Bhuana Ilmu Populer, 2005
Buku Teks