Nine Planets
The Nine Planets: Asteroids
A plethora of information about Asteroids. This site provides lots of in-text links to information, pictures of asteroids, a table full of information about asteroids, as well as links to more information about asteroids.
Nine Planets
The Nine Planets: Asteroids 253 Mathilde
This site explores what is currently known about the asteroid 253 Mathilde. Content includes an orbiting path, and composition. Links are provided throughout for additional information.
NASA
Nasa Space Science Data Archive: Asteroid 253 Mathilde
This site contains facts about the asteroid 253 Mathilde from the National Space Science Data Center at NASA.