History of the Peloponnesian War
Thucydides
Thucydides. The history of the Peloponnesian War, Volume 1-2. Dale, Henry, translator. London: Heinemann and Henry G. Bohn, 1851-1852.
But with regard to the facts of what was done in the war, I did not presume to state them on hearsay from any chance informant, nor as I thought probable myself; but those at which I was personally present, and, when informed by others, only after investigating them accurately in every particular, as far as was possible.