Neimark, Edith D.
Harcourt Brace Javanovich, 1987
Buku Teks
Gallup, George
McGraw-Hill, 1982
Buku Teks
edited by Matthew Beaumont
Blackwell, 2007
Buku Teks
Gironiere, Paul P. de la
A Burke-Mailhe Publication, 1972
Buku Teks
Twain, Mark, 1835-1910
New York Harper & Row Publisher 1962
Buku Teks