Luce, 1961
Buku Teks
Kennedy, Leslie W
McGraw-Hill Ryerson, 1983
Buku Teks
Kennedy, John F
Evanston, 1964
Buku Teks
Kennedy, Raymond
[publisher not identified], [date of publication not identified]
Buku Teks
Kennedy, George, author
McGraw-Hill, 1985.
Buku Teks