IVd. Score in a series:  Use the same style as a "Book in a Series."
(Note: DO NOT underline or italicize the series title) following MLA 8 p. 52 and 36

d. From a monument with series editor. 

Dufay, Guillaume. Zwölf geistliche und weltliche Werke. Edited by Heinrich Besseler, Mösler, 1932.  Das Chorwerk, Heft 19, edited by Friedrich Blume. Score.

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