Take a look at these. They're both e-available from the library.
Title The Spoken Work
Author Alward, Peter
Source Journal of Aesthetics and Art Criticism, vol. 62, no. 4, pp. 331-337, Fall 2004
Title Types, Continuants, and the Ontology of Music
Author Dodd, Julian
Source British Journal of Aesthetics, vol. 44, no. 4, pp. 342-360, October 2004