Rosenau, Milton D., Jr, author
Lifetime Learning, 1982
Buku Teks
Lee, Sidney, Sir, 1859-1926, author
IMS Pacific, 1985
Buku Teks
Crawford, Merle, author
McGraw-Hill, 2003
Buku Teks
edited by Larry Wizenberg
Dow Jones-Irwin, 1986
Buku Referensi
Crawford, C. Merle, author
McGraw-Hill/Irwin, 2000
Buku Teks