1. Proc. 1st Conf. on New Developments in Photodetection,1996
2. Burle Technologies Inc., 1000 North Holland Ave., Lancaster, PA 17601-5688, USA.
3. DEP Delft Electronische Producten, Dwazziewegen 2, Roden, Postbus 60, 9300 AB Roden, Netherlands.
4. Hamamatsu Photonics KK, 314-5, Shimokanzo, Toyooka-village, Iwata-gun, Shizuoka-ken, 438-01 Japan.
5. Litton Industries, Electric Tube Division, 1215 South 52nd Street, Temper, AZ 85218, USA.