Linked from
The 10 pages that link to Chromaticity, each with the reason it gives.
White pointNarrower topic: A white point specifies chromaticity, not the luminance of white.
Primary colorsRelated: Chromaticity diagrams show how selected primaries bound reproducible colors.
Display P3Related: The P3 primary chromaticities set Display P3’s gamut boundary.
Line of purplesNarrower topic: The line describes chromaticity rather than the intensity of light.