NF C97-618-3:1999 Electroacoustics. Simulators of human head and ear. Part 3 : acoustic coupler for the calibration of supra-aural earphones used in audiometry.
1999NF C97-618-3:1999 Electroacoustics. Simulators of human head and ear. Part 3 : acoustic coupler for the calibration of supra-aural earphones used in audiometry.