I want to know the answer to the following question:
What year did Joseph Dobrovský release a German-language grammar of Old Czech?
All the background I'm provided with is that "During the revival, in 1809 linguist and historian Josef Dobrovský released a German-language grammar of Old Czech entitled Ausführliches Lehrgebäude der böhmischen Sprache (Comprehensive Doctrine of the Bohemian Language).". Is that enough to answer the question?