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 Yvon WillersfiledCriticalYvon Willers
Priority to BE731976ApriorityCriticalpatent/BE731976A/fr
Publication of BE731976ApublicationCriticalpatent/BE731976A/fr