JOS, Vol 5, No 2 has a number of articles on the history of The Dietzgen Company and its slide rules. This JOS Volume also contains a four page insert by Bruce Babcock. His Dietzgen Catalog Matrix lists the various slide rule model numbers and the years they were listed in the catalogs. From 1897 to 1972. In 2009 two Articles written by Ian Lodge appeared in JOS, Vol 18, No 1 . The title was, Dietzgen 10-Inch Duplex Log-Log Slide Rule Chronology, Part I, to 1956 and Part II: 1956 to 1973.