The exact red, white, and blue colors to be used in the flag are specified with reference to the CAUS Standard Color Reference of America, 10th edition. Specifically, the colors are "White", "Old Glory Red", and "Old Glory Blue". The CIE coordinates for the colors of the 9th edition of the Standard Color Card were formally specified in JOSA in 1946. These colors form the standard for cloth, and there is no perfect way to convert them to RGB for display on screen or CMYK for printing. The "relative" coordinates in the following table were found by scaling the luminous reflectance relative to the flag's "white".