APA (7th ed.) Citation

Penn, E. J. (1973). Instant 2-way conversion: English, metric (5th ed.). E. J. Penn.

Chicago Style (17th ed.) Citation

Penn, E. Joe. Instant 2-way Conversion: English, Metric. 5th ed. Indianapolis, Ind.: E. J. Penn, 1973.

MLA (9th ed.) Citation

Penn, E. Joe. Instant 2-way Conversion: English, Metric. 5th ed. E. J. Penn, 1973.