Comfort, W. W., Tolles, F. B., & Bronner, E. B. (1986). The Quakers: A brief account of their influence on Pennsylvania (Rev. and reissued with additions.). University Park, Penn.: Pennsylvania Historical Association.

Comfort, William Wistar, Frederick Barnes Tolles, and Edwin B. Bronner. The Quakers: A Brief Account of Their Influence On Pennsylvania. Rev. and reissued with additions. University Park, Penn.: Pennsylvania Historical Association, 1986.

Comfort, William Wistar, Frederick Barnes Tolles, and Edwin B. Bronner. The Quakers: A Brief Account of Their Influence On Pennsylvania. Rev. and reissued with additions. University Park, Penn.: Pennsylvania Historical Association, 1986.