Taylor, Phillip M.
Routledge, 1997
Buku Teks SO
Paul C. Adams, Julie Cupples, Kevin Glynn, André Jansson and Shaun Moores, authors
Routledge, 2017
Buku Teks SO
John D.H. Downing, editor
SAGE Publications, 2011
Buku Referensi
Sandman, Peter M.
Prentice-Hall, 1976
Buku Teks SO
Francois, William E.
Grid Inc., 1977
Buku Teks SO