Parsons, Robert
Harper & Row, 1974
Buku Teks SO
Chou, Ya-Lun
Holt, Rinehart and Winston , 1972
Buku Teks
Grunig, Rudolf
Pringer, 2005
Buku Teks
edited by Anthony G. McGrew
Manchester University Press, 1985
Buku Teks
Radford, K.J.
Prushin-Hall, 1974
Buku Teks