P
PatentIndex
Search
Landscape
Sign in
Inventor
LUDWIG MAX
DE
2 patents
Patents
2 patents
US4757186A
Jul 12, 1988
Method which allows continued use of a credit card which is expired in time or value units
SIEMENS AG
37 citations
88
US4746786A
May 24, 1988
Method and apparatus for evaluating units stored on credit cards
SIEMENS AG
28 citations
88