Anderton, Charles H, author
Cambridge University Press, 2019
eBooks
Wilber, Charles K.
McGraw-Hill , 1992
Buku Teks
edited by Martin H. Wolfson, Gerald A. Epstein
Oxford University Press, 2013
Buku Teks
Isaak, Robert A.
Prentice-Hall, 1991
Buku Teks
Artikel Jurnal