[1]Howard Kahane, Logic and Philosophy: A Modern Introduction [Belmont: Wadsworth Publishing Co., 1990], p.270.

[2]Jan Lukasiewicz, Aristotle's Syllogistic From the Standpoint of Modern Formal Logic [Oxford: The Clarendon Press, 1957], p.15.

[3]Jonathan Lear, Aristotle and Logical Theory [Cambridge: Cambridge University Press, 1980], p.ix.

[4]Lear, p.2.