Thomas Corwin, Superintendent of Standard Weights and Measures, The Mendenhall OrderArxivat 2012-09-30 a Wayback Machine., publicada el 1893 com un apèndix de l'informe del U.S. Coast and Geodetic Survey.
Thomas Corwin, Superintendent of Standard Weights and Measures, The Mendenhall OrderArxivat 2012-09-30 a Wayback Machine., publicada el 1893 com un apèndix de l'informe del U.S. Coast and Geodetic Survey.