Gunnar Graarud starred in an opera from 1929-1937 known as what in german?
Gunnar Graarud:  After making his debut in 1919, he was a leading artist at the Berlin State Opera from 1924-1926 and at the Vienna State Opera from 1929-1937. Vienna State Opera: The Vienna State Opera (German: Wiener Staatsoper ) is an Austria opera house and opera company based in Vienna, Austria.
Wiener Staatsoper