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 Josef Sperka, Jiri SperkafiledCriticalJosef Sperka
Priority to CS868732ApriorityCriticalpatent/CS258566B1/cs
Publication of CS873286A1publicationCriticalpatent/CS873286A1/cs
Publication of CS258566B1publicationCriticalpatent/CS258566B1/cs