Columbia subject headings:
Interactive computer systems.
Interactive videos.
Telecommunication.
Teleconferencing.
Videotex systems.
Harvard subject headings:
Interactive computer systems.
Interactive videos.
Telecommunication.
Teleconferencing.
Videotex systems.
Princeton subject headings:
Interactive computer systems.
Interactive videos.
Telecommunication.
Teleconferencing.
Videotex systems.