1. The color science of dyes and pigments;McLaren,1986
2. Pliny the Elder, Historia Naturalis, 1929 (book IX, sections 60–65, chs." XXXVI–XLI as translated by Bailey).
3. Purple fish;Cole;Philosophical Transactions of the Royal Society,1685
4. The colourful past: origins, chemistry and identification of natural dyestuffs;Hofenk de Graaff,2004
5. Royal purple of Tyre;Lloyd;Journal of Near Eastern Studies,1963