Baker, Sidney MacDonald
Contemporary Books, 2003
Buku Teks
compiled and edited by Elaine Cumming
Jossey-Bass, 1970
Buku Teks
Williams, Anne
Butterworth-Heinemann , 1998
Buku Teks
White, Kevin
Sage , 2013
Buku Teks
Hahn, Dale B.
McGraw-Hill, 2002
Buku Teks