Lloyd, John, author
Rahat Books, 2007
Buku Teks
Wrenn, Chase B., 1974-, author
Polity, 2015
Buku Teks
Ferkiss, Victor C.
Braziller, 1969
Buku Teks
Larue, Gerald A.
Prentice-Hall, 1975
Buku Teks
Creel, Herrlee Glessner, 1905-1994, author
John Day, [date of publication not identified]
Buku Teks