Lauer, Robert H.
Allyn and Bacon, 1982
Buku Teks SO
edited by Nigel Parton
Routledge & Kegan Paul, 1996
Buku Teks
edited by Bob Pease and Jan Fook
Routledge, 1999
Buku Teks
Kirst-Ashman, Karen Kay
Cengage Learning , 2017
Buku Teks
Kirst, Ashman Karen Kay
Cengage Learning, 2013
Buku Teks