1. Acoustics. Reference zero for the calibration of audiometric equipment. Reference threshold of hearing under free-field and diffuse-field listening conditions Part 7, (15th April 1998) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (20 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗
2. Hearing aids. Magnetic field strength in audio-frequency induction loops for hearing aid purposes Part 4, (15th November 1998) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (10 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗