Mack, Maynard
W.W.Norton & Company INC, 1974
Buku Teks
New York : W.W. Norton & Company, 1970.
Buku Teks
Hardy, Thomas, 1840-1928, author
Dell, 1962
Buku Teks
Oberg, Erik, author
Industrial Press, 2012
Multimedia
edited by Kirsten Malmkjær
Routledge, 2004
Buku Referensi