There are provided a data recording medium, a reading device for reading the data recording medium, a recording device for reading the data recording medium and recording data to other media, and methods thereof able to prevent forgery without comparing visible information and data stored in a built-in...http://www.google.com/patents/US20040035934?utm_source=gb-gplus-sharePatent US20040035934 - Data recording medium, reading device, recording device, and methods thereof
