Roth, Robert F.
Chicago, Ill. Crain Books c. 1982,
Buku Teks
Bridgman, Robert F.
Oxford University Press, 1979
Buku Teks
Falmer Press, 1999
Buku Teks
Blythe, Jim, author
Prentice-Hall, 2000
Buku Teks
Eagle, Lynne, author
Taylor & Francis Group, 2015
Buku Teks