Cite
HARVARD Citation
Institution,, B. (1992) BS 6789-6.2:1989. Apparatus with one or moreparticular functions for connection to public switched telephonenetworks run by certain public telecommunications operators. Specification for series connected apparatus. Apparatushaving less than maximum allowable impairments.. [Online]. London : British Standards Institution. Available from: http://access.bl.uk/ark:/81055/vdc_100104117024.0x000001