Diels, Hermann, ed. Die Fragmente der Vorsokratiker. 3 volumes. 11th edition. Revised by Walter Krantz. Berlin: Weidmann, 1964.
This collection of the "opinions" of the Presocratic philosophers written in German is frequently cited and portions of it translated by twentieth-century scholars in their own analyses of the Presocratics.
Hussey, Edward. The Presocratics. New York: Charles Scribner's Sons, 1972, 168 p.
A book-length introduction to the history of Greek thought, from 600 B.C. to 400 B.C. Hussey stresses in the Preface that the book does not presuppose any knowledge of Greek and that it...
(The entire section is 511 words.)