Coontz, Sydney h.
London Routledge & Kegan Paul Ltd. 1957,
Buku Teks
Adelman, Irma, author
Stanford University Press, 1961
Buku Teks
Hutchinson, E.P., author
Houghton Mifflin, 1967
Buku Teks
Link, Robert G., author
Columbia University Press, 1959
Buku Teks
Beard, Charles A., author
Macmillan, 1957
Buku Teks