Louis E. Barbrow and Lewis V. Judson (1976). "Appendix 4 The international nautical mile"(PDF). Weights and Measures Standards of the United States, A brief history. NIST Physics Laboratory. Archived from the original(PDF) on 2007-09-26. Retrieved 2007-08-02.
Louis E. Barbrow and Lewis V. Judson (1976). "Appendix 4 The international nautical mile"(PDF). Weights and Measures Standards of the United States, A brief history. NIST Physics Laboratory. Archived from the original(PDF) on 2007-09-26. Retrieved 2007-08-02.