Barnum, Susan R.
Wadsworth, 1998
Buku Teks
Kumar, H.D.
Vikas Publishing House, 1997
Buku Teks
Sobti, R.C.
CRC Press, Taylor & Francis Group, 2009
Buku Teks
edited by Martin Fransman, Gerd Junne and Annemieke Roobeek
Blackwell, 1995
Buku Teks
Wiley-VCH, 2004
Buku Teks