1. Bafana A, Devi SS, Chakrabarti T (2011) Azo dyes: past, present and the future. Environ Rev 19:350–370
2. Booth G, Zollinger H, McLaren K, Sharples WG, Westwell A (2000) Dyes, general survey. Ullmann’s encyclopedia of industrial chemistry, vol 11. Wiley-VCH, Weinheim, pp 675–729
3. Zollinger H (2003) Color chemistry: synthesis, properties and applications of organic dyes and pigments, 3rd edn. Wiley-VCH, Weinheim
4. Garfield S (2002) Mauve: how one man invented a color that changed the world? Norton, New York
5. Colour index online. Available from
http://www.colour-index.org/
. Accessed 15 Jan 2019