Internal Optical Modulator
Ivan P. Kaminow
U.S. Patent 3,405,370. October 1968

Optical modulator
Charles E. Enderby and Richard M. White
U.S. Patent 3,393,954. July 1968

System, apparatus and method for improving stability of synchronous machines
Otto J. M. Smith
U.S. Patent 3,388,305. June 1968

Combined binary decoder-encoder employing tunnel diode pyramid-organized switching matrix
Joseph F. Kruy and Chittoor V. Ramamoorthy
U.S. Patent 3,387,298. June 1968