United States Patent 3159930
Inventors:
Allen, Dewar L.
O'malley, Jay W.
Publication Date:
12/08/1964
Assignee:
Allen, Dewar L.
O'malley, Jay W.
Other Classes:
229/74, 229/921, 206/831, 156/DIG.002, 206/459.500, 40/615
International Classes:
G09F3/02