11. Specification for direct acting indicating electrical measuring instruments and their accessories. (30th June 1978) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (55 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗
12. Specification for direct-acting electrical recording instruments and their accessories. (28th February 1975) Authors: British Standards Institution, Other Names: British Standards Institution, publisher. Record Type: Book Extent: 1 online resource (50 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗