Uta C. Merzbach: Georg Scheutz and the first printing calculator. Smithsonian Institute, Washington D.C. 1977, (Smithsonian Studies in History and Technology, 36) sil.si.edu (PDF; 30,9 MB).
Edwards Park: What a difference the Difference Engine made. From Charles Babbage’s calculator emerged today’s computer. In: Smithsonian magazine. Februar 1996 (web.archive.org [abgerufen am 4. November 2021]).