Sometimes it is difficult to locate microforms in HOLLIS. Try searching on the name of the holding library in the Creator field.
And here are some ideas for how to discover music manuscripts at Harvard:
- check HOLLIS
- check HOLLIS for Archival Discovery
- have someone at Houghton look in the Theatre Collection Autograph File
- look it up in Chadwyck-Healy
- look it up in Barbara Marienholz-Wolff's Music Manuscripts at Harvard
- try ArchiveGrid