Book: Hutchins, Catherine E., et al. 1983 Arts of the Pennsylvania Germans.
• Published as fig. 261, p. 264.Book: Ames, Kenneth L. 1977 Beyond Necessity: Art in the Folk Tradition.
• Published on p. 72, fig. 78.Article: Hubbert, Ruthann. 1982 "Francis Portzline (1771-1857)". The Snyder County Historical Society Bulletin. 19-29.
Book: Earnest, Russell D. & Earnest, Corinne P. 1997 Papers for Birth Dayes: Guide to the Fraktur Artists and Scriveners. 2 vols. 909.
• Published on p. 626. For more info. on Portzline, see pp. 623-626.