Hilley, M., & Olson, L. F. (2002). Piano for pleasure: A basic course for adults (4th ed.). Schirmer/Cengage.
Chicago-viite (17. p.)Hilley, Martha, ja Lynn Freeman Olson. Piano for Pleasure: A Basic Course for Adults. 4th ed. Boston, Mass: Schirmer/Cengage, 2002.
MLA-viite (9. p.)Hilley, Martha, ja Lynn Freeman Olson. Piano for Pleasure: A Basic Course for Adults. 4th ed. Schirmer/Cengage, 2002.
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