1. Penn-Ohio Rail System Story: a History of an Electric Railway of the Mahoning and Shenango River Valleys of Eastern Ohio and Western Pennsylvania
. Robert S. Korach. Forty Fort: Harold E. Cox, 2006.
2. CERA Bulletin No. 108, Electric Railways of Northeastern Ohio.
Joseph M. Canfield. Chicago: Central Electric Railfan’s Association, 1965.
3. Ohio Trolleys.
Kenneth S. P .Morse. Baltimore: Sutherland Press, 1960.
4. From Small Town to Downtown: A History of the Jewett Car Company, 1893-1919 (Railroads Past and Present)
. Brough, Lawrence A., and Graebner, James H. Indiana University Press, 2004.
5. The Electric Pullman: A History of the Niles Car & Manufacturing Company.
Lawrence A. Brough. Indiana University Press, 2013.
Personal site of Dr. Harold E. Cox, a source for the car builders order lists — http://streetcars.telcen.com/
Ohio Trolley Lines
at Don's Depot.
Penn Ohio System
at (new) Dave's Electric Railroads.