Cornell University
Cornell University: Isometries and Patterns
Shows the different kinds of isometries and patterns, and gives examples of each kind. Includes definitions, terminology, examples, and problems.
Cornell University
Cornell University: Cornell Office of Distance Learning
This is the home page for the office of distance learning at Cornell University. A course catalog and several other distance learning related links are provided on this site.
Cornell University
Cornell University: Astronomy: Electromagnetism and Charge
This site from Cornell University provides a very short, very telling comparison of matter and charge. This is a good site to check out on the subject, with a chart diagram to help with further information.