-
3599988
-
Patent number 3,599,988
-
Issue date Aug 17, 1971
-
G11 - INFORMATION STORAGE
-
3425701
-
Patent number 3,425,701
-
Issue date Feb 4, 1969
-
G11 - INFORMATION STORAGE
-
3367664
-
Patent number 3,367,664
-
Issue date Feb 6, 1968
-
G11 - INFORMATION STORAGE
-
3363909
-
Patent number 3,363,909
-
Issue date Jan 16, 1968
-
G11 - INFORMATION STORAGE