Simmers, Louise M., author
Delmar Cengage Learning, 2009
Buku Teks
Keller, Edward A., author
John Wiley & Sons, 2014
eBooks
Ziman, John, author
Cambridge University Press, 1994
Buku Teks SO
Sage Publications , 2018
Majalah, Jurnal, Buletin
University of technology,
Majalah, Jurnal, Buletin