Thompson, June M., author
Westview Press, 1990
Buku Teks
Walsh, Warren Bartlett, author
The University of Michigan Press, 1958
Buku Teks
The University of Chicago Press, 1983
Buku Teks
Harvard University Press, 1955
Buku Teks
Gallagher, Matthew P., author
Frederick A. Preager, 1963
Buku Teks