1. The Measurement of Appearance, John Wiley, New York, 1975, p. v.
2. Colour and other aspects of appearance, presented at the Second National Conference of the Colour Society of Australia, October 1989.
3. Ref. 1, p. 4.
4. Fundamentos de Teoría de la Delimitación, Facultad de Arquitectura y Urbanismo, Universidad de Buenos Aires, 1984, p. 1.
5. Cesia: A system of visual signs complementing color