1. Indigo;Balfour-Paul,2006
2. The colourful past: origins, chemistry and identification of natural dyestuffs;Hofenk de Graaff,2004
3. Koekboya. Natural dyes and textiles. A colour journey from Turkey to India and beyond;Böhmer,2002
4. Present status of natural dyes;Gulrajani;Indian J. Fibre Text. Res.,2001
5. Dye plants and dyeing;Cannon,1994