Fanning's Illustrated Gazetteer of the United States.... (New York: Phelps, Fanning & Co., 1853), 58.
BUREAU COUNTY, situated toward the north part of Illinois, on the northwesterly side of Illinois river. Area, 648 square miles. Watered by Bureau creek and Winnebago lake. Seat of justice, Princeton. Pop. in 1840, 3,067; in 1850, 8,841.