(F/E/S) : French, English and Spanish version; See also French version in LA CLASSIFICATION INTERNATIONALE DES BREVETS : CONFERENCE DIPLOMATIQUE DE STRASBOURG : CONSEIL DE L'EUROPE : OMPI; See also English version in THE INTERNATIONAL PATENT CLASSIFICATION : STRASBOURG DIPLOMATIC CONFERENCE : CONCIL OF EUROPE : WIPO; 1e Session : Estrasburgo, 15-24 de marzo de 1971: IPC/DC/1-2;.