Spinage, Clive A., author
Springer, 2012
eBooks
Dodge, Dorothy, author
D. Van Nostrand, 1966
Buku Teks
Hunter, J.A.
Harper & Brothers, Publishers, 1954
Buku Teks
edited by Herbert J. Spiro
Prentice-Hall, 1967
Buku Teks
Murray, Rachel, author
Cambridge University Press, 2004
Buku Teks