* Knox, MacGregor and Murray, Williamson, "The Dynamics of Military Revolution, 1300–2050" (Cambridge, 2001)* Kubik, Timothy R. W., "Is Machiavelli’s Canon Spiked?
* Knox, MacGregor and Murray, Williamson, "The Dynamics of Military Revolution, 1300—2050" (Cambridge, 2001)* Kubik, Timothy R. W., «Is Machiavelli’s Canon Spiked?