Tarulis, Albert N.
University of Notre Dame Press, 1959
Buku Teks
Hellmann, Donald C., author
University of California Press, 1969
Buku Teks
edited by Harley D. Balzer
Westview Press, 1991
Buku Teks
Moo,Harriet L
Princeton University press, 1945
Buku Teks
Moore, Harriet
Princeton University Press, 1945
Buku Teks