73262869
May 19, 1980
Feb 15, 1983
Ceramic Sprockets, Bearings and Gears for Industrial Machines; and, Ceramics Used in Engines for Jet Airplanes and Parts Thereof
MachineryCeramics for the Manufacture of Computers and Communication Satellites, and for Vacuum Tubes and for Equipment for the Carrying Out of Commercial Processes
Electrical and Scientific Apparatus