1. Blake, A. Proc. 9th Int. Joint Conf. on Artif. Intell. 973–976 (1985).
2. Blake, A. & Brelstaff, G. J., Proc. 2nd Int. Conf. comp. Vis. 394–403 (Institute of Electrical and Electronics Engineers, Washington DC, 1988).
3. Bülthoff, H. H. & Mallot, H. A. J. opt. Soc. Am. 5, 1749–1758 (1988).
4. Phong, B. T. Communs. Ass. comput. Mach. 18, 311–317 (1975).
5. Beck, J. Surface Color Perception (Cornell University Press, New York, 1972).