Colour names, data visualization chart - Chris Harrison (source: Image Quest)
18th C. color wheel - Moses Harris (source: Image Quest)
Theory of Colours, Etching 181 - J. W. Goethe
NEWTON'S COLOR DISK Moderate Spin - Richard Megna (source: Image Quest)
Colour Scale / 20 Shades of Blue - Rene Digeon (source: Image Quest)
First chromatic circle: pure colours, M - Rene Digeon (source: Image Quest)