Question: Rotraud Hansmann was a singer in the recordings by which Austrian conductor, particularly known for his historically informed performances of music from the Classical era and earlier?
Sentence (from "Nikolaus Harnoncourt"): Starting out as a classical cellist, he founded his own period instrument ensemble, Concentus Musicus Wien, in the 1950s, and became a pioneer of the Early Music movement.
Relevant evidence: No