See this example properly formatted in the QUT Cite tool.
Standard in-text citation examples are in Getting started - In-text citation.
Composer. Year. Title. Place of publication: Publisher.
John, Elton and Bernie Taupin. 2004. Greatest hits, 1970-2002. Milwaukee: H. Leonard.
Published music scores are treated like books. If only one score is used from an edited anthology, treat as for a chapter in an edited book. If found online, substitute the URL or database name for the publishing details.