O`Donnell, Angela M., author
John Wiley & Sons, 2012
Buku Teks
De Cecco, John P.
Prentice-Hall, 1974
Buku Teks
Slavin, Robert E., author
Paramount Publishing, 1994
Buku Teks
Schwartz, Lita Linzer, author
Holbrook Press, 1972
Buku Teks
Kathleen M. Cauley, editor
Dushkin, 2000
Buku Teks