A greetings or the like card (144), characterized by a board (2) forming at least part of the card and in that the board is a distributed mode acoustic radiator having a transducer (9) mounted wholly and exclusively on the radiator to vibrate the radiator to cause it to resonate....http://www.google.fr/patents/US6181799?utm_source=gb-gplus-shareBrevet US6181799 - Greetings or the like card
