6. Bibliography

Sources in alphabetical order:

Borowski,S. (2012, May 21). Trebuchets and their modern use. Retrieved Sep 1, 2013, from http://membercentral.aaas.org/blogs/scientia/trebuchets-and-their-modern-use

Federation of American Scientists. (n.d.). Federation of American Scientists. Retrieved July 10, 2013, from http://www.fas.org/programs/ssp/man/usw

Johnson, S. (n.d.). Modern Uses of a Catapult. eHow. Retrieved July 10, 2013, from http://www.ehow.com/info_8597229_modern-uses-catapult.html

Poza (2011, March 29). Ping Pong Ball Catapult. Retrieved July 5, 2013, from http://www.instructables.com/id/Ping-Pong-Ball-Catapult/?ALLSTEPS

(n.d.). All about Catapults . Retrieved July 10, 2013, from http://www.catapults.info/

(n.d). Modern Day Catapults. Physics of Catapults. Retrieved July 5,2013, from https://sites.google.com/site/physicsofcatapults/home/modern-day-catapults