The Prestel directory.
British Telecom.
Birmingham : Directel Ltd. on behalf of British Telecommunications,
1983-
Description based on: Oct. '83 issue.
Issues for Mar./Apr. 1987-  published as a supplement to Connexions by Marathon Videotex Ltd. on behalf of British Telecom for registered users of Prestel and subscribers to Connexions.
Prestel (Videotex system)
Prestel user