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便用式新型电子计算器
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2001-02-15
수식입력키보드
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1982-02-27
Electronic cash register
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1916-01-20
Improvements in or relating to Calculating Machines.
JPH0455692U
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1992-05-13
KR900000456B1
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1990-01-30
전자식 금전등록기의 프린팅 제어방법
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Numerical data input apparatus
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TI Hands It to You