Fredrickson, George M., author
Univ. of California Press, 2000
Buku Teks
Greene, Thomas H., author
Prentice-Hall, 1984
Buku Teks
Richards, Graham, author
Routledge, 1997
Buku Teks
Robert, Ron E., author
Mosby, 1979
Buku Teks
Wood, James L., author
Wadsworth, 1982
Buku Teks