Entered from booking ledger and New York Times concert listing and review. "MUSIC NOTES." New York Times (1923-), Nov 21 1959, p. 27. ProQuest. Web. 1 Oct. 2021. "GERTRUDE JANSSEN GIVES SONG RECITAL." New York Times (1923-), Nov 22 1959, p. 82. ProQuest. Web. 1 Oct. 2021.