Estimated number of nuclear weapons by Country, 1945–2008. J. HotezPeter 2013 <p>Sources: <a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0000680#pntd.0000680-1" target="_blank">[1]</a> and <a href="http://en.wikipedia.org/wiki/List_of_states_with_nuclear_weapons" target="_blank">http://en.wikipedia.org/wiki/List_of_states_with_nuclear_weapons</a>.</p>