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Application filed by Ahti Kalervo HeikkinenfiledCriticalAhti Kalervo Heikkinen
Priority to FI750987ApriorityCriticalpatent/FI51633C/fi
Publication of FI51633BpublicationCriticalpatent/FI51633B/fi
Application grantedgrantedCritical
Publication of FI51633CpublicationCriticalpatent/FI51633C/fi