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Publication of BE407861ApublicationCriticalpatent/BE407861A/fr
Procede pour conferer a un substrat destine a l'impression mecanique et manuelle et a la reprographie, la propriete d'etre selectivement et simultanement effacable, indelebile nettoyable, lavable et modifiable
Dispositif permettant l'identification permanente de tous les documents administratifs officiels ou non, publics ou prives et assurant aussi l'inviolabilite de la non-falsification