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.
As they skirted the coast they touched at Cephallenia, where they made a descent upon the territory of the Cranians; here deceived by the inhabitants through some sort of agreement they lost a few of their men by an unexpected attack of the Cranians, and finally, after they had got out to sea with considerable difficulty, managed to get back home.
In the course of the same winter the Athenians, following the custom of their fathers, celebrated at the public expense the funeral rites of the first who had fallen in this war.
The ceremony is as follows. The bones of the departed lie in state for the space of three days in a tent erected for that purpose, and each one brings to his own dead any offering he desires.
On the day of the funeral coffins of cypress wood are borne on wagons, one for each tribe, and the bones of each are in the coffin of his tribe. One empty bier, covered with a pall, is carried in the procession for the missing whose bodies could not be found for burial.