LEGO MINDSTORMS: MINDSTORMS EV3 (45502) for sale online | eBay
Motors: EV3 vs NXT
NXT® motor internals
Introduction to the EV3 Meduim motor | FLLCasts
Lego Mindstorms 9842 NXT Servo Motor (141J7) | eBay
Amazon.com: LEGO Mindstorms EV3 L-Servo Motor : Toys & Games
Amazon.com: LEGO MINDSTORMS EV3 Building Set Includes 3 Interactive Servo Motors, Remote Control, Improved And Redesigned Color Sensor, Redesigned Touch Sensor, Infrared Sensor And 550+ LEGO Technic Elements : Toys & Games