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Application filed by Helmut Graupner, Wolfhart BahrsfiledCriticalHelmut Graupner
Priority to DD20444778ApriorityCriticalpatent/DD135120B1/de
Publication of DD135120A1publicationCriticalpatent/DD135120A1/de
Publication of DD135120B1publicationCriticalpatent/DD135120B1/de