Foster, Lynn E
Prentice-Hall, 2006
Buku Teks
University of technology,
Majalah, Jurnal, Buletin
Linda A. Macaulay, Ian Miles, Jennifer Wilby, Yin Leng Tan, Liping Zhao, Babis Theodoulidis, editors
[Springer, ], 2012
eBooks
Derry, Gregory N.
Princeton University Press , 1999
Buku Teks
Sawyer, R. Keith
Oxford University Press, 2006
Buku Teks