1. ASTM D1535. Standard Practice for Specifying Color by the Munsell System. ASTM International, West Conshohoken, Pennsylvania, http://www.astm.org.
2. ASTM D2244. Standard Practice for Calculation of Color Tolerances and Color Differences from Instrumentally Measured Color Coordinates. ASTM International, West Conshohoken, Pennsylvania, http://www.astm.org.
3. ASTM D4086. Standard Practice for Visual Evaluation of Metamerism. ASTM International, West Conshohoken, Pennsylvania, http://www.astm.org.
4. ASTM E284. Standard Terminology of Appearance. ASTM International, West Conshohoken, Pennsylvania, http://www.astm.org.
5. ASTM E308. Standard Practice for Computing the Colors of Objects by Using the CIE System. ASTM International, West Conshohoken, Pennsylvania, http://www.astm.org.