Mayer, Frederick
A History of Ancient of Medieval Philosophy / Frederick Mayer.
American Book Company, 1950
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Armstrong, A.H.
An introduction to ancient philosophy
Newman Press, 1949
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Oxford studies in ancient philosophy; Vol.III
edited by Julia Annas
Clarendon Press , 1985
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Blackson, Thomas A.
Ancient Greek philosophy : from the presocratics to the hellenistic philosophers
Wiley-Blackwell, 2011
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Oxford studies in ancient philosophy; Vol. II
edited by Julia Annas
Clarendon Press, 1984
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