http://library.thinkquest.org/CR0215468/rockets.htm
http://www.grc.nasa.gov/WWW/K-12/TRC/Rockets/history_of_rockets.html
http://quest.arc.nasa.gov/space/teachers/rockets/history.html
http://exploration.grc.nasa.gov/education/rocket/rktstage.html
http://en.wikipedia.org/wiki/Rocket
http://dssresources.com/cases/spaceshuttlechallenger/ShuttleChalleng_crew_portrait.jpg
http://www.grc.nasa.gov/WWW/K-12/TRC/Rockets/history_of_rockets.html
http://quest.arc.nasa.gov/space/teachers/rockets/history.html
http://exploration.grc.nasa.gov/education/rocket/rktstage.html
http://en.wikipedia.org/wiki/Rocket
http://dssresources.com/cases/spaceshuttlechallenger/ShuttleChalleng_crew_portrait.jpg