Eduard Zeller 
Outlines of the History of Greek Philosophy [PDF ebook] 

First published in 2000. This is Volume X of ten in the International Library of Philosophy in a series on Ancient Philosophy. Written in 1931, this is the thirteenth edition of outlines of the history of Greek philosophy. The author’s aim was to provide students with the contents of the different philosophic systems and the course of their historical development which should contain all essential features, and also to put into their hands the more important literary references and sources.