For help searching for music scores please see the Music Subject Guide.
To locate a piano sonata score use an 'advanced search' in the library catalogue. Try the following search terms:
eg: cimarosa sonat* piano
Note the truncation symbol "*" used to retrieve English and non-English titles for "sonata" as well as the plural used in the subject heading: e.g. Sonatas (Piano).
Check the bibliographic record to identify the work's opus or musicological number.
If the number is not given, check for the key of the work.
If unsure, check in Oxford Music Online (Grove Dictionary of Music and Musicians).
For the example search above, check the results list: if the score is in C minor – see call no. P34 CIM 2.