Entered from program calendar and New York Times concert listing and review. "Concert and Opera Programs of the Week." New York Times (1923-Current file): 1. Apr 20 1952. ProQuest. Web. 19 Mar. 2014. "Miss Sigurdson Gives Piano Program Here." New York Times (1923-Current file): 89. Apr 27 1952. ProQuest. Web. 19 Mar. 2014.