원본: Helen Marlais. "A very enlightened approach, which is certainly worth considering for very young pianists. Sheet Music. Piano. PF.
번역: 헬렌 Marlais. 피아노에 성공하기 - 준비 수준 메리 크리스마스 도서. 악보. 계획. Students play pieces on the black keys, Middle C, and "almost" Middle C position.