M-2063 Wiecker, Otho. "The Story of an artist while executing a portrait-sketch, the first from life, of Abraham Lincoln, in June 1860, at Springfield, Ill., and his close association, experience and intimacy with the President which came to light in 1911, fifty-one years after, and a description of the Portrait itself." Otho Wiecker, Antiquary, Harvard Square oppo. Harvard College at Cambridge in Massachusetts, Sub- 2, Box: 26. James Wills Bollinger Papers, MsC0036. University of Iowa Special Collections. https://aspace.lib.uiowa.edu/repositories/2/archival_objects/5974 Accessed April 29, 2025.