. "Entered from booking ledger and New York Times concert listing and review. The correct program order is uncertain.\r\n\"Who Makes Music and Where.\" New York Times (1923-), 13 Apr. 1969, p. 1. ProQuest. Web. 13 May 2025.\r\nHenahan, Donal. \"Ko Iwasaki, Cellist, and Sister, Shuku, Pianist, in Sonata Recital.\" New York Times (1923-), 15 Apr. 1969, p. 42. ProQuest. Web. 13 May 2025." . . "1969-04-14T20:30:00"^^ . . "Ko Iwasaki, Cello, and Shuku Iwasaki, Piano" . . . . . "duo recital" . .