Book: Minardi, Lisa. 2024 Americana Insights.
• Published: p. 37Book: Stopp, Klaus. 1998 The Printed Birth and Baptismal Certificates of the German Americans. 4.
• Published under Stopp 637, p. 130.Article: Weiser, Frederick S. 1988 "Ach Wie ist die Welt so Toll! The mad, lovable world of Friedrich Krebs.". Der Reggeboge: Journal of the Pennsylvania German Society. 22 (2): 49-88.
Book: Earnest, Russell D. & Earnest, Corinne P. 1997 Papers for Birth Dayes: Guide to the Fraktur Artists and Scriveners. 2 vols. 909.
• For more on Krebs, see pp. 460-467.