Library of Congress classification is for books and serials. Microforms, audio and video recordings, CDs and DVDs, and pre-catalog materials use different call number systems. Display periodicals are shelved alphabetically by title.
Library of Congress Classification
The main system in use is the Library of Congress classification system, which was implemented in 1969. Call numbers are alpha-numeric. The first line of each number is made up of one, two, or three letters of the alphabet followed by two or more lines of letters and numbers.
Materials cataloged in the Library of Congress classification are shelved in one continuous sequence regardless of language. In Gowen Stacks, this sequence begins on Floor 2M and continues to Floor 1M. Folio books (over 30 cm. in height) are shelved on Floor 1.
Examples of a Library of Congress call number:
Materials that cannot be fully cataloged upon receipt are assigned numbers based on the order in which they arrive in the library. They are then shelved in numerical order in separate sections by language. The pre-cataloging process enables library users to have quick, direct access to new acquisitions. All books in the pre-cataloged (pre-cat) section can be located in the catalogs under primary author and title.
Pre-cat books are all shelved on Floor 1 of Gowen Stacks. Examples of pre-cat numbers are given below. Please note that current materials use the seven digit hyphenated numbers: