In the Music Division, the vast majority of dealer catalogs are classified under the old Billing classification system where the call number/classmark begins with:
Even recently-received catalogs (with rare exceptions) will be filed under this classmark.
(The asterisk is part of the classmark and must be used when searching the catalog under "call number" even though these classmarks do not have any numbers associated with them.)
Although a search in the catalog on the call number *MCD will reveal only several such catalogs, the Music Division has many thousands of dealer catalogs. The vast majority of these are filled alphabetically under the name of the dealer (either an individual or a firm). They are not inventoried and are not findable through the catalog. They have also not been subject to official cataloging, so names of individuals and firms have not been regularized based on standard use.
One can submit a call slip with the classmark *MCD and put down the name of a dealer to see what the Music Division has. In the case of publishers who used their first name as part of their corporate name (such as Otto Haas), one should submit slips with a variety of options:
Be aware that some dealers’ catalogs may be located in other divisions of the New York Public Library.
Dealer catalogs dating from before 1820 will be Special Collections items. Many of their classmarks will begin with the prefix Mus. Res., as in:
Mus. Res. *MCD
The significance of certain catalogs has led the Music Division to catalog them separately and sometimes individually. For example: