Standard reference zero for the calibration of pure tone air conduction audiometers, Specification for a standard reference zero using an acoustic coupler complying with BS 4668— 8 стр.
Specification for a reference zero for the calibration of pure-tone audiometers, Data for earphone coupler combinations maintained at certain standardizing laboratories
Specification for a reference zero for the calibration of pure-tone audiometers, Data for earphone coupler combinations maintained at certain standardizing laboratories
