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Application filed by Friedrich Liepe, Gerhard Langhans, Hartmut Weissgaerber, Eberhard HaeberfiledCriticalFriedrich Liepe
Priority to DD20703278ApriorityCriticalpatent/DD138038B1/en
Publication of DD138038A1publicationCriticalpatent/DD138038A1/en
Publication of DD138038B1publicationCriticalpatent/DD138038B1/en