RUNGE-KUTTA 4th ORDER METHOD

http://numericalmethods.eng.usf.edu/topics/runge_kutta_4th_method.html

Lazy Singleton

http://www.yoda.arachsys.com/csharp/singleton.html

Momentum and collisions – background material

http://www.animations.physics.unsw.edu.au/jw/momentum.html#time
http://www.physics.isu.edu/~hackmart/momentumcollisions100.PDF

VPython Video Tutorials

http://vpython.erikthompson.com/

Vector Math for 3D Computer Graphics

http://chortle.ccsu.edu/VectorLessons/vectorIndex.html

Python doodles

Physics in Python
http://metakatie.wordpress.com/2009/02/01/double-pendulum/