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Publication date
Publication of BE795124ApublicationCriticalpatent/BE795124A/fr
B43—WRITING OR DRAWING IMPLEMENTS; BUREAU ACCESSORIES
B43L—ARTICLES FOR WRITING OR DRAWING UPON; WRITING OR DRAWING AIDS; ACCESSORIES FOR WRITING OR DRAWING
B43L1/00—Repeatedly-usable boards or tablets for writing or drawing
B43L1/12—Repeatedly-usable boards or tablets for writing or drawing having translucent writing surfaces producing visual impressions by co-operation with backing members