Retrieved 2014-11-21. ↑ Chase, Kenneth (2003), Firearms: A Global History to 1700, Cambridge University Press, ↑ Kendall F. Haven, 100 greatest science inventions of all time p.30-32 ↑ Ley, Geschichte der Rakete, 1932. ↑ "Rockets and Missiles: The Life Story of a Technology", A. Bowdoin Van Riper,p.10 ↑ "CONRAD HAAS Raketenpionier in Siebenbürgen (german)". Sibiweb.de. Retrieved 2012-12-10. ↑ a diminutive of rocca "distaff", itself from a Germanic source. ↑ English rocket from c.