Harvard Business School Press, 2001
Buku Teks
Holt, Katherine E.
[;American Society for Training & Development Press, American Society for Training & Development Press], 2003
eBooks
Albritton, Rosie L.
Cool Libraries, 1990
Buku Teks SO
edited by Sunil Mani, Henny Romijn
United Nations University Press, 2004
Buku Teks
Retno Kusumastuti
Universitas indonesia, faculty of social and political sciences, 2015
Artikel Jurnal