SPICKER, M. (1986). The master-pieces of vocalization: A graded series of vocal studies for all voices for Soprano. G. Schirmer. Inc.
Chicago-viite (17. p.)SPICKER, Max. The Master-pieces of Vocalization: A Graded Series of Vocal Studies for All Voices for Soprano. G. Schirmer. Inc, 1986.
MLA-viite (8. p.)SPICKER, Max. The Master-pieces of Vocalization: A Graded Series of Vocal Studies for All Voices for Soprano. G. Schirmer. Inc, 1986.
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