1. Keiner, L.E. www.kingfish.coastal.edu/physics, used by permission of the author.
2. The Colour Index, Society of Dyers and Colourists, www.colour-index.org.
3. ETAD, ‘ETAD Information on the 19th Amendment of the Restrictions on the Marketing and Use of Certain Azocolourants’, www.etad.com/information.
4. Colour in textile effluents – the origins of the problem;Pierce;Journal of Society of Dyers and Colourists,1994
5. Decolorization of wastewater;Hao;Critical Reviews In Environmental Science and Technology,2000