General principles for classification and shelflisting follow. In all cases, catalogers should take into account pre-existing call numbers when assigning new ones. Try to follow existing patterns whenever feasible.
See LC M Class schedule for more information
In copy cataloging, class number in record is usually used
Occasionally class numbers will need to be assigned, using the Library of Congress M Classification, or rarely some other class, such as N or P
Generally the first Cutter is for author (taken from 100 field) and the second for title (taken from 245 or 240 field)
If the work is entered under title (no 100), the title Cutter is the only one assigned
Exceptions:
Some classes specify the first Cutter (e.g., bibliographies) or first two Cutters
In some cases the first Cutter is assigned for the person the work is about, e.g.: Biographies
Discographies
Bibliographies of specific composers or performers
Festschriften
In most call numbers, the final element will be the year of publication
Some series are classed together (M2, M3 and occasionally others). In these the call number will be the same for all parts of the set with the volume number being the final element. These items are usually accompanied by a paper slip from Acquisitions that indicates the call number for the set.
For multipart monographs (multiple items on one bibliographic record) volume designation will be in the item record.
Scores with distinctive titles will generally be shelflisted in the same manner as books, using one Cutter for composer and a second for title
If the work has an opus no. or thematic index no. in the uniform title, this will usually replace a Cutter. Check for existing patterns before making final decision
If there is no opus or thematic index number, add one of the following, in the following order of preference:
1. Serial no.
2. Key (abbreviate major as maj., minor as min.
3. Date of composition in parenthesis
4. Double Cutter by title or editor, etc.
For collections of works by one composer where the class number is equivalent to the uniform title (piano music, songs, etc.) assign a second Cutter based on editor, compiler, arranger or publisher, unless another arrangement is already in place.
Complete works of one composer will generally have only one Cutter for author (M3)
As with books, most score call numbers end with the year of publication
Exceptions: In some cases the last element will be Score or Parts if separate records have been used.
AS for books, scores may be part of a series classed together. In this case the final element will be the volume number of the set.