1. Marx, Karl, 1867, Das Kapital: Kritik der politishchen Oekonomie, (Verlag von Ott Meissner: Hamburg)
2. See the October 1987 and September 1991 issues of Scientific American for a forecast of hardware, software and networks.
3. Two of the Bell operating companies plan to have ISDN 90% installed by 1994 and the other five 50% installed by then. See: Bell, T., 1992, Telecommunications, IEEE Spectrum, Jan, pp 36–38
4. Timms, S., 1989, Broadband Communications: The Commercial Impact, IEEE Network Magazine, July
5. Lubliner, O., 1989, ISDN Development in France, Telecommunications, Jul, pp 19–24