See PostScript: Language Reference Manual (also known as the Red book) by Adobe Systems, Incorporated, Addison-Wesley, Reading, MA, 1985, for all the gory PostScript detail.
For a good introduction to halftones and dithering see the classic text on computer graphics, Computer Graphics: principles and practice2nd edition, by J. Foley, A. van Dam, S. Feiner, and J. Hughes, Addison-Wesley, 1990.
For an excellent in-depth article on resolution enhancement, see "Enhancing Laser-Printer Resolution" by Bradley Dyck Kliewer, in the March 1992 issue of Byte magazine.
From Belinda Collins, "Evaluation of Colors for Use on Traffic Control Devices," NISTIR 88-3894 National Institute of Standards and Technology, Gaithersburg, MD, Nov. 1988.
For a terrific overview of the possibilities and uses of spot color, see "See Spot Color" by Eda Warren in Aldus Magazine, Vol. 3, No. 2, Jan./Feb. 1992.
See "Sampling the Color Matching Spectrum," by Jan V. White, in Computer Publishing Magazine, Jan. 1991, for a wonderful description of colormatching systems.
For the complete specifications and guidelines of EPS files refer to Encapsulated PostScript Files Specification Version 2.0 available from the PostScript\xa8 Developer Tools & Strategies Group of Adobe Systems, Inc.
The FaceSaver project was primarily the responsibility of Lou Katz, a former Director of USENIX, although many people had a hand in the success of FaceSaver over the years. A short overview of the project in action is covered in "The FaceSaver Project" in the July/Aug. 1989 issue of ;login:.
For the details on psfig, see Psfig A Ditroff Preprocessor for PostScript files, Internal Report, Computer and Information Science Department, University of Pennsylvania, Philadelphia, PA. The easiest place to get the document is from one of the many Internet archives that provides the psfig software.
