1. Johnson A, ‘Correlating proofs to production print’, Pira study, 1980
2. ISO 12647-1, ‘Graphic technology — Process control for the manufacture of halftone colour separations, proof and production prints — Part 1: Parameters and measurement methods’, 1996
3. ISO 5-3, ‘Photography — Density measurements — Part 3: Spectral conditions’, 1995
4. Tritton K,Colour Control in Lithography, 113, 218, Pira International, UK, 1997, ISBN: 1 85802 036 0
5. Field G G,Color and its Reproduction, 107-9, GATF, Pittsburgh, 1998, ISBN: 0 88362 088 X