Quigley, Harold S., author
University of Minnesota Press, 1956
Buku Teks
Woll, Peter, author
Little, Brown, 1984
Buku Teks
Woll, Peter, author
Little, Brown, 1965
Buku Teks
Manley, John F., author
Macmillan, 1976
Buku Teks
edited by Steven Muller
Macmillan, 1963
Buku Teks