Turner Whitted. An improved illumination model for shaded display. In Thomas A. DeFanti, Bruce H. McCormick, Bary W. Pollack, Norman I. Badler, S. H. Chasen, editors, Proceedings of the 6th Annual Conference on Computer Graphics and Interactive Techniques, SIGGRAPH 1979, Chicago, Illinois, USA, August 8-10, 1979. pages 14, ACM, 1979. [doi]
Abstract is missing.