Bibliography

http://www.historyplace.com/worldwar2/timeline/v1.htm

http://www.v2rocket.com/start/chapters/vonbraun.html

http://en.m.wikipedia.org/wiki/V-1_flying_bomb

http://en.m.wikipedia.org/wiki/V-2_rocket

http://en.m.wikipedia.org/wiki/  Timeline_of_space_exploration