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http://en.wikipedia.org/wiki/Atomic_nucleus
http://en.wikipedia.org/wiki/Nuclear_weapon
http://www.3rd1000.com/history/nuclear.htm
http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/nucuni.html
http://www.nuffieldfoundation.org/practical-physics/developing-model-ato...
http://chemistry.mtu.edu/~pcharles/SCIHISTORY/08nuclearatom.html
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