This template is used for digitized scans from Biblioteka Warszawskie Towarzystwo Muzyczne accessible from Polish Music Heritage in Open Access. The full name of this institution is Biblioteka, Muzeum i Archiwum Warszawskiego Towarzystwa Muzycznego im. Stanisława Moniuszki, Warszawa. Details about items from the library can also be found at RISM.
Without any template variables, the link points to a browseable list of digitized scans from Biblioteka Warszawskie Towarzystwo Muzyczne.
To link to specific scans, see the usage documentation at Template:PMH. The PMH template uses the same template variable convention, but is more generic, since it's not specific to any particular institution involved in the scanning project.
