Purfeest, Charles. “Old Seppmann Mill, 1864 – 1890”, Paper, 1965. SMHC Manuscript Collection 1327, Southern Minnesota Historical Center, Memorial Library, Minnesota State University, Mankato.

Purfeest, Charles. “Old Seppmann Mill, 1864 – 1890”, Paper, 1965. SMHC Manuscript Collection 1327, Southern Minnesota Historical Center, Memorial Library, Minnesota State University, Mankato. https://archivesspace.lib.mnsu.edu/public/repositories/4/resources/239 Accessed May 09, 2025.