DIN EN ISO 11821:1997-08 Acoustics - Measurement of the in situ sound attenuation of a removable screen (ISO 11821:1997); German version EN ISO 11821:1997
1997DIN EN ISO 11821:1997-08 Acoustics - Measurement of the in situ sound attenuation of a removable screen (ISO 11821:1997); German version EN ISO 11821:1997
1997DIN EN ISO 11821:1997 Acoustics - Measurement of the in situ sound attenuation of a removable screen (ISO 11821:1997); German version EN ISO 11821:1997