Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Gratzmuller JfiledCriticalGratzmuller J
Priority claimed from FR790603Aexternal-prioritypatent/FR1238763A/en
Publication of BE573947ApublicationCriticalpatent/BE573947A/en