History of the Peloponnesian War
Thucydides
Thucydides, Vol. 1-4. Smith, Charles Foster, translator. London and Cambridge, MA: Heinemann and Harvard University Press, 1919-1923.
It was in this way, then, that the Athenians got their walls built, and came to be engaged upon their other fortifications, immediately after the withdrawal of the Persians.
Meanwhile Pausanias son of Cleombrotus was sent out from Lacedaemon in command of the Hellenes with twenty ships from Peloponnesus, accompanied by thirty Athenian ships and a multitude of other allies.
They nmade also an expedition against Cyprus, subduing most of it, and afterwards, at the time of Pausanias' leadership, besieged Byzantium, which the Persians then field, and took it.