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1973-04-24
Typewriter carriage and ribbon field control for error correction
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1956-02-14
Proportional ribbon feed mechanism
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1960-05-10
Printing mechanism
GB362527A
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1939-12-19
Combined typewriting and account
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1968-12-10
Multicolor printing device for business machines and equipment
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1935-01-08
Overdraft control of ribbon mechanism
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1940-06-04
Calculating machine
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1938-12-27
Cash register
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1931-08-04
Cash register
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1943-03-09
Special character and amount printing mechanism
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1934-12-11
H kaufmann
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1964-01-14
Printing mechanism
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1930-01-07
Duplicate-printing mechanism for calculating and like machines
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1952-04-29
Interlock between control members
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1933-09-05
Combined type writing
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1950-08-22
Accounting machine
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1924-12-24
Method of and apparatus for mechanical book-keeping
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1930-01-07
gubelmann
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1932-05-10
Combined typewriting
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1962-07-04
Document sorting and accounting systems and apparatus
GB530120A
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1937-08-10
Bookkeeping machine
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1919-04-29
Cipher-printing mechanism.