Dibner, Mark D.
McGraw-Hill, 1989
Buku Teks
Allinson, Gary D.
University California Press, 1975
Buku Teks
Sobti, R.C., author
CRC Press, Taylor & Francis Group, 2009
Buku Teks
edited by Martin Fransman, Gerd Junne and Annemieke Roobeek
Blackwell, 1995
Buku Teks
Barnum, Susan R., author
Wadsworth, 1998
Buku Teks