RT Book T1 Three logicians: Aristotle, Leibniz, and Sommers and the syllogistic A1 Englebretsen, George 1942- LA English PP Assen PB van Gorcum YR 1981 UL https://ixtheo.de/Record/040233022 CN B491.L8 SN 90-232-1815-9 K1 Aristotle K1 Leibniz, Gottfried Wilhelm, Freiherr von K1 Sommers, Frederic Tamler K1 Logic : History K1 Logic K1 Syllogism