The primary sources of a musical work can include the following:

Autograph / Holograph (the composer's own manuscript)

Copies (handwritten by a relative, student, colleague, or professional copyist; or, in the case of medieval works, by monastic scribes)

First edition (typically published in consultation with the composer)

Early editions (printed during the composer's lifetime)

Early editions (edited by a relative, student, or other person close to the composer, after the composer's death)

Scholarly editions (edited by a scholar or performer known for their knowledge / interpretation of the composer)

Collected editions (the composer's complete works, published in a scholarly edition that shows the variant readings (differences) in the above sources)

Learn more about primary sources and how to interpret them here.