^Doukas, Ozzie, ed. (1989). The Pennsylvania Manual. Vol. 109. Harrisburg: Pennsylvania Department of General Services. p. 640. ISBN0-8182-0130-4.
^Schehr, Elizabeth, ed. (2005). The Pennsylvania Manual. Vol. 117. Harrisburg: Pennsylvania Department of General Services. pp. 7–26. ISBN0-8182-0304-8.