Gould, Nick, author
Routledge, 2016
Buku Teks
Nina Rovinelli Heller, Alex Gitterman, editor
Routledge, 2011
Buku Teks
Saxton, John, Prof.
Routledge, 2011
Buku Teks
Robert C. Hyzy, editor
Springer International Publishing, 2017
eBooks
Anderson, David
Macmillan, 1982
Buku Teks