Rothenberg, Lawrence S.
Cambridge University Press, 1992
Buku Teks SO
Alexander, Robert M., 1972-
Thomson/Wadsworth, 2006
Buku Teks
Peterson, Christian Philip
Routledge, 2012
Buku Teks SO
Matthews, Donald R.
The University of North Carolina Press, 1960
Buku Teks SO
Smucker, Bob
Jossey - Bass Publishers, 1991
Buku Teks SO