A method of and an apparatus for reading a manually fed data carrier are disclosed. The data carrier has at least one line of coded positions and is fed manually past reader means including at least one pair of reader means which viewed in the direction of motion of the data carrier are spaced apart...http://www.google.de/patents/US3976857?utm_source=gb-gplus-sharePatent US3976857 - Method and an arrangement for reading coded information from a data carrier
