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Publication of BE690254ApublicationCriticalpatent/BE690254A/xx
G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
G06K1/00—Methods or arrangements for marking the record carrier in digital fashion
G06K1/12—Methods or arrangements for marking the record carrier in digital fashion otherwise than by punching
G06K1/128—Methods or arrangements for marking the record carrier in digital fashion otherwise than by punching by electric registration, e.g. electrolytic, spark erosion