Follow the citation convention for citing multivolume works with authors and/or editors.Chicago Manual, section 14.122
Though not appearing here, insert a hanging indent on every line after the first line.
Bibliography order of elements: Composer Last, Name First Name. Title of Score Volume. Edited by First Name Last Name. Vol. (#) of Title of Series, edited by First Name Last Name. City: Publisher, Year.
Note: here, "title of series" refers to the title of the collected edition. If your volume is part of a subseries (meaning, the title page indicates that the volume is part of a series), then you do need to indicate the series number; see example below)
Bibliography example: Verdi, Giuseppe. Il Trovatore. Libretto by Salvadore Cammarano. Edited by David Lawton. Series 1, vol. 18a., Works of Giuseppe Verdi, edited by Philip Gossett. Chicago: University of Chicago Press, 1992.
Footnote example: Johann Hermann Schein, Cantional oder Gesangbuch Augsburgischer Konfession 1627/1645 Teil 1, ed. Adam Adrio, vol. 2 of Johann Hermann Schein neue Ausgabe samtlicher Werke, ed. Adam Adrio (Kassel: Barenreiter, 1965).