Keuffel & Esser 4045 Mannheim Simplex Slide Rule

Chicago citation style
Keuffel & Esser Co. Keuffel & Esser 4045 Mannheim Simplex Slide Rule. ca 1915. Retrieved from the Digital Public Library of America, http://collections.si.edu/search/results.htm?q=record_ID%3Anmah_1214625&repo=DPLA. (Accessed November 21, 2018.)
APA citation style
Keuffel & Esser Co, (ca 1915) Keuffel & Esser 4045 Mannheim Simplex Slide Rule. Retrieved from the Digital Public Library of America, http://collections.si.edu/search/results.htm?q=record_ID%3Anmah_1214625&repo=DPLA
MLA citation style
Keuffel & Esser Co. Retrieved from the Digital Public Library of America <http://collections.si.edu/search/results.htm?q=record_ID%3Anmah_1214625&repo=DPLA>.
Note: These citations are programmatically generated and may be incomplete.