Andresen, Tetel Julie, author
Routledge, 1990
Buku Teks
Risjord, Norman K., author
Prentice-Hall, 1985
Buku Teks
Tindall, George Brown, author
WW Norton , 2013
Buku Teks
Parkes, Henry Bamford
Alfred A. Knoft, 1968.
Buku Teks
Risjord, Norman K., author
Prentice-Hall, 1985
Buku Teks