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.
Thus Sitalces son of Teres, king of the Thracians, became an ally of the Athenians, as also did Perdiccas son of Alexander, king of the Macedonians.