Bowser, eileen, author
Macmillan Library reference USA, 1990
Buku Referensi
Koszarski, Richard, author
Macmillan Library Reference USA,, 1990
Buku Referensi
Levy, Emanuel
New York University Press, 1999
Buku Teks
Musser, Charles, author
Macmillan Library reference USA,, 1990
Buku Referensi
Kolker, Robert, author
Oxford University Press, 2000
Buku Teks