ANSI/IEEE Std260.1:1993 American National Standard Letter Symbols for Units of Measurement ( SI Units, Customary Inch-Pound Units, and Certain Other Units)
This standard covers letter symbols for units of measurement.
ANSI/IEEE Std260.1:1993 history
1993ANSI/IEEE Std260.1:1993 American National Standard Letter Symbols for Units of Measurement ( SI Units, Customary Inch-Pound Units, and Certain Other Units)