1. Loughrey K (2005) Overview of color analysis. Unit F5.1. In: Wrolstad RE, Acree TE, Decker EA, Penner MH, Reid DS, Schwartz SJ, Shoemaker CF, Smith D, Sporns P. (eds) Handbook of food analytical chemistry-pigments, colorants, flavors, texture, and bioactive food components. Wiley, NY
2. Berns RS (2000) Billmeyer and Saltzman’s principles of color technology, 3rd edn. Wiley, NY
3. Campbell NA, Reece JB, Mitchell LG (1999) Biology, 5th edn. Benjamin/Cummings, Addison Wesley Longman, Menlo Park, CA
4. Loughry K (2000) The measurement of color, Chap 13. In: Francis FJ, Lauro GJ (eds) Natural food colorants. Marcel Dekker, NY
5. Wyszecki G, Stiles WS (1982). Color Science. Concepts and methods. Quantitative data and formulae, 2nd edn. John Wiley & Sons, Inc, NY.