The Persistence of Vision Raytracer is a high quality, totally free tool for creating stunning 3D graphics. It is available in official versions for all versions of Windows, for DOS, the Macintosh, i86 Linux, SunOS, and Amiga. The source code is available for those wanting to do their own ports.
www.povray.org

Sophisticated Global Illumination standalone rendering engine, free for personal use and available for Windows (Win32). A Linux version should be coming soon.
www.3dvirtualight.com

Photorealistic scenery rendering software. Terragen is a work-in-progress scenery generator for Windows. At this stage of its development, Terragen is free for personal non-commercial use.
www.planetside.co.uk

The Ultimate Resource for Computer Graphic Artists, Web Developers, CAD Architects, and Scientific Visualization. Thumbnailed 3D-Models and Textures in various formats, Galleries, Tutorials, Advertisement, VIP-Lounge.
www.3dcafe.com

Raytracing News Guide "Light Makes Right" compiled by Eric Haines.
Volume 14, Number 1 has a short article about WinOSi written by Phil Dutre.
www.acm.org/tog/resources/RTNews/html/

The Concise Guide to Global Illumination Algorithms. An effort to bring together most of the useful formulas and equations for global illumination algorithms in computer graphics. This site has a link to WinOSi!
www.graphics.cornell.edu/~phil/GI/

Research Associate, Stanford University: Articles about global illumination, photon mapping. Has many sample images.
graphics.stanford.edu/~henrik/papers/

Introductions, formulas, algorithms and sample images about Rendering & Geometry.
www.swin.edu.au/astronomy/pbourke

"The good-looking textured light-sourced bouncy fun smart and stretchy page". Many very good tutorials about computer graphics (programming).
freespace.virgin.net/hugo.elias/

3D Geometry Specifications, Moving Image Resources.
www.dcs.ed.ac.uk/~mxr/gfx/3d-lo.html

Real-Time-Raytracer with source, written by Thomas Ludwig, Tutorial about Real-Time-Raytracing.
www.cfxweb.net/~lyc/lray.html

The directory contains some tests (vmd and jpg files), 2 vmd "templates" that others may or may not find useful, the little WinOSi logo scene which was made by Erik Robson (rendered in WinOSi).
fiction.pair.com/3d/

Very interesting german site containing a WinOSi discussion group.
forum.jotero.com

Theory and Practice
Alan Watt, Mark Watt
Addison Wesley Publishing Company, acm press
ISBN 0-201-54412-1

Henrik Wann Jensen
A K Peters Ltd.
ISBN 1-56881-146-0

Symbolic Shape Design using Interval Analysis
John M. Snyder
Academic Press, inc.
ISBN 0-12-654040-3