CIE 1976 L*a*b* colour difference 
difference between 2 colour stimuli defined as the Euclidean distance between the points representing them in the L*a*b* space and calculated as:
Equivalent term: "CIELAB colour difference"
See also CIE 15 Colorimetry
See also ISO 11664-4:2008(E)/ CIE S 014-4/E:2007 Colorimetry - Part 4: CIE 1976 L*a*b* Colour Space