How to Do Library Research

The following shows you how to find a book with a Library of Congress (LC) Classification number.

LC call numbers begin with letters of the alphabet. Each letter stands for a broad subject grouping; each letter and number that follow the first letter narrow down the subject. No two books have exactly the same call number. Numbers used in the following examples are hypothetical.

The first line just needs to be treated alphabetically. Thus,

Line two is read in straight numerical order; numbers range from 1 to 9999 and are shelved accordingly:

Line three is often misunderstood. Line 3 is the Cutter number (named after Charles A. Cutter). It is a DECIMAL number, not a whole number like the second line. Therefore, .K79 comes before .K8. (There is usually a decimal point before the letter on that line, but even when the label does not show the point, line three is treated as a decimal number.)

Line four is called the Double Cutter number. It too is treated as a decimal number even though there is no decimal point showing:

Sometimes call numbers do not appear vertically, but horizontally.

Whether vertically or horizontally arranged, the Cutter number and Double Cutter numbers are always treated as decimal numbers.

One important thing to remember with call numbers is the rule, "nothing comes before something":

QA 349 .M613 W4 goes on the shelf before QA 349 .M613 W4 1993

A second way of describing call numbers follows

A call number is an address for a book or other material. In LC classification, numbers before the decimal point are read in ordinary numerical sequence, but after the decimal point, they are read decimally and not as whole numbers. The following represents how these books are arranged on the shelf:

Because there are two books with the same class number, SB 411, they are arranged by the number after the decimal point. To find a book on the shelf, look at each element of the call number.

It may be helpful to think in terms of money: 45 1/2 cents is less than 56 cents which is less than 60 cents.

The following example of call numbers represents a shelf of literature books arranged in the order in which they appear on the shelves.

The Library of Congress Subject Headings (LCSH) provides an alphabetical listing of authorized or preferred terms established by the Library of Congress since 1898. These "official" terms should be used when doing Subject searches in Colorado State University's library catalog. LCSH was published in large volumes with red covers, but is now available online in PDF files on the Library of Congress Web site.

Many names of places and people (i.e., proper nouns) are not listed in LCSH, however, they may be used as subject headings.

Use References

USE references are made FROM an unauthorized or non-preferred term TO an authorized or preferred term. They are made for synonyms and for older and variant forms of headings. For example,

Componets of LCSH Entries

Subject heading is in boldface.

CODE (May Subd Geog) or (Not Subd Geog) (in italics) indicates whether or not the heading can be subdivided geographically.

LC class numbers are given when there is a close correspondence between the subject heading and the LC classification. (Approximately 36% of headings have class numbers.)

Scope note gives guidance in the meaning or application of the heading. (Approximately 4000 scope notes appear in LCSH.)

References express the relationship between terms:

Example LCSH entry:

Subdivisions

Subdivisions combine a number of different concepts into a single subject heading. Only a fraction of all possible heading and subdivision combinations are listed in LCSH. Most subdivisions are indicated by a general reference under the heading that is the same as the subdivision as in the following example:

Periodicals

SA subdivision Periodicals under specific subjects, e.g. Engineering--Periodicals;
United--States--History--Periodicals

There are four types of subdivisions:

For details on what subdivisions are used for literary authors, look up the pattern heading "Shakespeare, William" for possibilities (some of the subdivisions don't make sense in the context of Shakespeare, but using only one author saves a lot of space).

See the "Table of Pattern Headings" for other terms used as patterns for possible subdivisions. (Found in introductory information for the LCSH in Vol. 1.)

Choice of Terms in LCSH

Frequently, LC subject headings are not the terms most commonly used. Examples of how different the terms are follow:

In using the library catalog, LC Subject Headings are listed under "SUBJECTS" in the full record of the item. When you find a useful item, do additional searches for subjects you find listed there.

Searching the Library Catalog

To search for items in the library catalog using the LCSH term, type S from the main menu and then type in the term(s). From the catalog on the web, select "LC Subjects" and then type in your term(s).

Colorado State University's government documents are shelved in Superintendent of Documents (SuDoc) classification call numbers. Materials are arranged by issuing agency, not by subject. See Finding a Document on the Shelf for how to read these numbers.