US patent 4826646, Bussard, Robert W., "Method and apparatus for controlling charged particles", issued 1989-05-02, assigned to Energy/Matter Conversion Corporation, Inc.
Hosted by Dr. David Livingston (May 7, 2007). The Space Show. Episode Broadcast 709 (Special Edition) with guests Dr. Robert W Bussard, Thomas A Ligon. {{cite episode}}: External link in |number= (help)