A flexible resilient magnetic particle type information card capable of correctly reading information thereon after such card has been bent double on itself and creased, said card comprising a flexible base, a layer of uniformly distributed magnetic particles thereon, and a flexible overlayer of nonmagnetic...http://www.google.de/patents/US3946206?utm_source=gb-gplus-sharePatent US3946206 - Magnetic-type information card and method and apparatus for encoding and reading
