Gm 03 : An incorrect symbol for the gram (See below). The correct symbol is g. In engineering, "gm" is sometimes used to distinguish "gram mass" from "gram force" (gf). This practice is not recommended
Russ Rowlett (Director), How Many? A Dictionary of Units of Measurement, Center for Mathematics and Science Education University of North Carolina, USA 2005. http://www.unc.edu/~rowlett/units/dictA.html, (Unit of Meas and Covr Factors - Amer) {608}