Eder, Phanor J., author
Oxford University Press, 1950
Buku Teks
Webb, Michael, 1937-, author
Uneverse publishing, 2001
Buku Teks
Foxley, Alejandro
University of California Press , 1983
Buku Teks
Wiarda, Howard J., author
Wardword, 1995
Buku Teks
Westview Press, 1980
Buku Teks