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Vic Stathopoulos. Space Exploration.
http://members.lycos.co.uk/spaceprojects/spaceexploration.html 2003

Leonard David. "Deep Space Exploration - Looking for Planetary Paydirt".
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Astronomy Department at Cornell University. Space Exploration and Astronauts.
http://curious.astro.cornell.edu/space.php 2002

NASA. Liftoff to Space Exploration.
http://liftoff.msfc.nasa.gov/ 2003

Calvin J. Hamilton. History of Space Exploration
http://www.solarviews.com/eng/history.htm 2001

Family Education Network, Inc. Space Exploration
http://www.infoplease.com/ipa/A0001346.html 2003

J.D. Knight. Sea and Sky: Space Exploration.
http://www.seasky.org/ 1997