APA (7th ed.) Citation

Kells, L. M., Kern, W. F., & Bland, J. R. (1943). The log log duplex decitrig slide rule, no. 4081: A manual. Keuffel & Esser.

Chicago Style (17th ed.) Citation

Kells, Lyman M., Willis F. Kern, and James R. Bland. The Log Log Duplex Decitrig Slide Rule, No. 4081: A Manual. New York: Keuffel & Esser, 1943.

MLA (9th ed.) Citation

Kells, Lyman M., et al. The Log Log Duplex Decitrig Slide Rule, No. 4081: A Manual. Keuffel & Esser, 1943.