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                        3890473
                    
                                            
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                                    Patent number 3,890,473
                                
 
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                                    Issue date Jun 17, 1975
                                
 
                        
                                                                
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                        3836728
                    
                                            
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                                    Patent number 3,836,728
                                
 
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                                    Issue date Sep 17, 1974
                                
 
                        
                                                                
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                        3737898
                    
                                            
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                                    Patent number 3,737,898
                                
 
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                                    Issue date Jun 5, 1973
                                
 
                        
                                                                
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                        3536839
                    
                                            
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                                    Patent number 3,536,839
                                
 
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                                    Issue date Oct 27, 1970
                                
 
                        
                                                                
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                        3397288
                    
                                            
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                                    Patent number 3,397,288
                                
 
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                                    Issue date Aug 13, 1968
                                
 
                        
                                                                
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                        3387094
                    
                                            
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                                    Patent number 3,387,094
                                
 
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                                    Issue date Jun 4, 1968
                                
 
                        
                                                                
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                        3246318
                    
                                            
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                                    Patent number 3,246,318
                                
 
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                                    Issue date Apr 12, 1966
                                
 
                        
                                                                
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                        3158694
                    
                                            
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                                    Patent number 3,158,694
                                
 
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                                    Issue date Nov 24, 1964
                                
 
                        
                                                                
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                        3142054
                    
                                            
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                                    Patent number 3,142,054
                                
 
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                                    Issue date Jul 21, 1964
                                
 
                        
                                                                
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                        3141068
                    
                                            
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                                    Patent number 3,141,068
                                
 
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                                    Issue date Jul 14, 1964
                                
 
                        
                                                                
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                        3140431
                    
                                            
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                                    Patent number 3,140,431
                                
 
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                                    Issue date Jul 7, 1964
                                
 
                        
                                                                
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                        3089131
                    
                                            
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                                    Patent number 3,089,131
                                
 
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                                    Issue date May 7, 1963
                                
 
                        
                                                                
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                        3028452
                    
                                            
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                                    Patent number 3,028,452
                                
 
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                                    Issue date Apr 3, 1962
                                
 
                        
                                                                
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                        2885478
                    
                                            
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                                    Patent number 2,885,478
                                
 
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                                    Issue date May 5, 1959
                                
 
                        
                                                                
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                        2827625
                    
                                            
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                                    Patent number 2,827,625
                                
 
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                                    Issue date Mar 18, 1958
                                
 
                        
                                                                
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                        2797407
                    
                                            
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                                    Patent number 2,797,407
                                
 
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                                    Issue date Jun 25, 1957
                                
 
                        
                                                                
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                        2787689
                    
                                            
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                                    Patent number 2,787,689
                                
 
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                                    Issue date Apr 2, 1957
                                
 
                        
                                                                
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                        2764634
                    
                                            
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                                    Patent number 2,764,634
                                
 
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                                    Issue date Sep 25, 1956
                                
 
                        
                                                                
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                                    G11 - INFORMATION STORAGE
                                 
                        
                 
             
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                        2732434
                    
                                            
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                                    Patent number 2,732,434
                                
 
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                                    Issue date Jan 24, 1956
                                
 
                        
                                                                
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