Eagleton, Clyde
New York University press, 1945
Buku Teks
Greenwood, Gordon, 1913-1986
University of Queensland, 1976
Buku Teks
Winpisinger, William W.
Colorado Westview Press, 1989
Buku Teks
Dunlap, Peter T.
Routledge; Taylor & Francis Group, 2008
Buku Teks
Oxford Oxford University Press 1987,
Buku Teks