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.)
Publication of BE599887ApublicationCriticalpatent/BE599887A/xx
Priority claimed from US7384Aexternal-prioritypatent/US3090717A/en
Priority claimed from FR851799Aexternal-prioritypatent/FR1279062A/fr
