Reference books can be found here, in the Music and Dance Reference Collection.
Here is the guide to reference books, found on the end of the first shelf of the Reference Collection, nearest the copy machine. Of note, dictionaries and encyclopedias are found from ML100-ML109. Bibliographies, including thematic catalogues of composers and discographies (bibliographies of sound recordings), are found from ML112.8-ML158.8. See Dictionaries & Encyclopedias and Other Reference Resources in this guide for reference books and online resources particularly relevant to keyboard literature.
ML books contain literature about music. This includes reference books, like dictionaries, encyclopedias, and bibliographies, as well as history and criticism.
ML410 is the single call number that takes up the most shelf space. These are biographies of composers, including analyses of composers' works.
MT books include music study and instruction, including music education, music theory, and methods for teaching. Notice that bound periodicals (older issues of journals and magazines) are found past the MT books.