The Geometry of the Sphere
- This material was the text for part of the Advanced Mathematics course in the High School Teachers Program at the IAS/Park City Mathematics Institute at the Institute for Advanced Study during July of 1996.
- http://math.rice.edu/~pcmi/sphere/

Geometry Machine
- 3D virtual reality geometrical images of vectors, lines and planes. Needs a VRML viewer or plugin such as live3D.
- http://www.scit.wlv.ac.uk/~cm1993/geometry/INTRO.HTM