Question: The CASA 2. 111 was a medium bomber derived from what German aircraft that was designed by Siegfried and Walter Gunter at Heinkel Flugzeugwerke in 1934?
Sentence (from "Albatros L 76"): The plane had wooden dual-spar wings with plywood skins supported by N-type struts and a fabric-covered fuselage made of welded steel tubing.
Relevant evidence: No