Adams, Katherine H.
Mayfield Publishing Company, 2000
Buku Teks SO
Marcus, Leonard J.
Jossey-Bass, 1995
Buku Teks SO
Rockefeller College Press, 1988
Buku Teks
edited by Romulo Pinheiro, Lars Geschwind, Francisco O. Ramirez, Karsten Vrangbaek
Emerald, 2016
eBooks
Fasel, Diane K.
Pathways, 2000
Buku Teks