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
Priority claimed from GB26080/69Aexternal-prioritypatent/GB1187153A/en
Application filedfiledCritical
Priority claimed from DE1760655Aexternal-prioritypatent/DE1760655B2/de
Publication of BE712289ApublicationCriticalpatent/BE712289A/fr