Burnet, John (1957) [1892]. Early Greek Philosophy. The Meridian Library. (reprinted from the 4th edition, 1930; the first edition was published in 1892). An online presentation of the Third Edition can be found in the Online Books Library of the University of Pennsylvania.
Kirk, G.S. (1957). The Presocratic Philosophers. Cambridge: University Press. Unknown parameter |coauthors= ignored (|author= suggested) (help) (subsequently reprinted)
G. E. R. Lloyd. Early Greek Science: Thales to Aristotle.
Nahm, Milton C. (1962) [1934]. Selections from Early Greek Philosophy. Appleton-Century-Crofts, Inc.
Pliny the Elder; The Natural History (eds. John Bostock, M.D., F.R.S. H.T. Riley, Esq., B.A.) London. Taylor and Francis, Red Lion Court, Fleet Street. (1855). Online version at the Perseus Digital Library.
