Bloom, Floyd E.
W.H. Freeman & Co. , 1988
Buku Teks SO
edited by Donna Coch, Kurt W. Fischer, Geraldine Dawson
Guilford Press, 2007
Buku Teks
Keyes, Charles Don
Routledge, 1999
Buku Teks SO
Obler, Loraine K.
Cambridge University Press, 1999
Buku Teks SO
Atkins, Michael D.
Macmillan, 1980
Buku Teks