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.
But whether the oracle meant the greatest festival in Attica or somewhere else he did not go on to consider, and the oracle did not make it clear. For, in fact, the Athenians also have a festival in honour of Zeus Meilichius, the Diasia, as it is called, a very great festival celebrated outside the city, whereat all the people offer sacrifices, many making offerings[*](A scholiast suggests cakes (πέμματα) made in the forms of animals.) peculiar to the country instead of victims. But Cylon, thinking that he was right in his opinion, made his attempt.
And the Athenians, when they were aware of it, came in a body from the fields against them and sitting down before the Acropolis laid siege to it.