Keylor, William R., 1944-
Oxford University Press, 1996
Buku Teks
Gossel, Peter, author
Taschen, 2001
Buku Teks
Black, C.E., author
Alfred A. Knopf, 1966
Buku Teks
Woodham, Jonatham M., author
Oxford University Press, 1997
Buku Teks
Dulles, Foster Rhea, author
Houghton-Mifflin, 1945
Buku Teks