The search for a composer's archives can be time-consuming because archival materials could be scattered across multiple libraries, museums, and private collections. Below are suggestions to help you focus your search:

• Grove Music Online article for the composer.
• A published research guide, if one has been published for the composer you have chosen.
• Directory of music research libraries (1983-)
• Outdated but can be helpful in identifying collections to search on the Internet.

• Online Archive of California.(OAC) 

OAC provides free public access to detailed descriptions of primary resource collections maintained by more than 200 contributing institutions including libraries, special collections, archives, historical societies, and museums throughout California.

• The Website of an organization devoted to the composer.
• WorldCat search: Example: Richard Wernick
• Articles about the composer's works
• Wikipedia "External Links" at the end of an article about the composer

Collected works volumes

The accompanying notes or separate Revisionsbericht associated with each volume provides details which document the composer's intentions regarding a specific musical work.  Reference may be made to a significant primary source.

Composer's letters

The Music Library acquires selectively published collections of letters by composers.  Search the composer's name as a SUBJECT in the online catalog. Limit your search by the SUBJECT  WORD "correspondence".  If there is an index in the volume there may be a separate section under "works" OR there may be a separate index for musical works.

Manuscripts and early editions:

Information:

A research guide, if one has been published for the composer you have chosen,  may provide helpful information and give you direction.

The thematic catalog for the composer you have selected also may give you information about extant manuscripts and early editions.

The composer's works list in the Grove Music Online may also give you information about extant manuscripts.

Music manuscript facsimiles:

The Music Library has a strong collection of music manuscript facsimiles.  Most begin with the Dickinson call no "04". Check the Vassar Library-Search Catalog and the Music Library card catalog for a full listing.

Digital facsimiles of music manuscripts have been created by libraries throughout the world. Many have been collected in DIGITIZED MUSICAL SCORES AVAILABLE ON THE INTERNET  under the "Manuscripts" tab at the left.  Begin with the Music Treasures Consortium which allows the searching of multiple, but not all, collections.