APA (7th ed.) Zitazioa
Heerema, E. (1984). Progressive class piano: A practical approach for beginners (2nd ed.). Califonia state Univ.
Chicago Style (17th ed.) Zitazioa
Heerema, Elmer. Progressive Class Piano: A Practical Approach for Beginners. 2nd ed. Northbridge: Califonia state Univ, 1984.
MLA (9th ed.) Zitazioa
Heerema, Elmer. Progressive Class Piano: A Practical Approach for Beginners. 2nd ed. Califonia state Univ, 1984.
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