1. K. Ganzhorn, Elektronische Rechenanlagen 15, 263 (1973).
2. R. L. Mattson, Applied Optics 13, 755 (1974).
3. L. D. Dickson and R. L. Soderstrom, to be published in Applied Optics with Proceedings of Conf. On Laser Engineering and Appl., Washington D.C., May 28, 1975. A closely related manuscript has also been submitted to the IBM J. Res. Develop.
4. W. V. Smith, Electronic Information Processing (Artech House, Dedham, Mass., 1974).
5. S. Triebwasser, Proceedings of the 5th Conf. (1973 International) on Solid State Devices, Tokyo, 1973, Supplement to the Journal of the Japan Society of Applied Physics, Vol. 43 (1974).