Butler, Pamela E.
Harper & Row Publishers, 1981
Buku Teks
Weston, Joy, author
Gramedia, 2005
Buku Teks
Emerson, Rupert, author
Cambridge: Harvard University Press, 1960
Buku Teks
Sijthoff & Noordhoff , 1980
Buku Teks
Emerson, Rupert, author
Harvard University Press, 1962
Buku Teks