History of the Peloponnesian War
Thucydides
Thucydides. History of the Peloponnesian War. Crawley, Richard, translator. London and Toronto: J. M. Dent and Sons Ltd.; New York: E. P. Dutton and Co., 1914.
On their right were the Thebans and those of their province, in the center the Haliartians, Coronaeans, Copaeans, and the other people around the lake, and on the left the Thespians, Tanagraeans, and Orchomenians, the cavalry and the light troops being at the extremity of each wing. The Thebans formed twenty-five shields deep, the rest as they pleased.
Such was the strength and disposition of the Boeotian army.