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FYS 10 - Power of Tradition, Forces of Change: Call Numbers

Understanding LC Call Numbers

Most LC call numbers have four parts:

  • General Subject (represented by one to three letters)
  • Narrower Topic (represented by a number)
  • Cutter number (represents author, title, or corporation; named for Charles Ammi Cutter, who developed the alphanumeric table for them)
  • Year of Publication

Call number example

Title: Pharmacology for Women's Health
Editor: Tekoa L. King

RG Gynecology and Obstetrics
131 Gynecologic drugs
.P43 Cutter number (based on title, “Pharmacology”)
2001 Publication Year


How to Read Call Numbers

The formatting of the call number depends on where it is displayed. On the book's spine label, the parts of the call number are listed vertically, as in the image above. In SuperSearch, the call number is displayed on a single line, and may not have spaces between parts.


How Call Numbers are Arranged on the Shelf

Each line of a call number is read differently

The first line consists of 1 to 3 letters and is read alphabetically. The following are in the correct order:

A  B  BF  C  CD  D  DA  DAW  G  GE

The second line is a whole number and is read as a numeral. This number may contain a decimal. The following are in the correct order:

1  9  38  39  133  725  725.9  1225  9756

The third line (and perhaps fourth, if there are multiple Cutters) can be the trickiest to read. It consists of a letter, which is ordered alphabetically, followed by numbers, which are read as a decimal. So, just as the decimal .525 comes before the decimal .7, so does the cutter .B525 come before the cutter .B7. The following are in the correct order:

.B5  .B525  .B6  .B679  .B7  .C3  .C337  .C4  .C5877

The last line is the four-digit year of publication, and is read in chronological order.

1889  1902  1975  1980  2001  2017

In addition, there may be letters and numbers indicating the book’s order in a series. Here are some common examples:

V.1 Volume 1
Pt. 3 Part 3
ser. A Series A
no. 22 Number 22
Suppl. Supplement


Call Number Variations

It's important to note that not all call numbers have exactly four lines representing the same information. It depends on the nature of the work. Here are some other examples:

Multiple Cutter Numbers

A second Cutter number is used when there are many works on a topic or by an author, and the works cannot be represented in sufficient detail by a single Cutter. The second cutter number does not have a leading decimal point.

Example of a call number with multiple Cutter numbers

Title: The Road
Author: Cormac McCarthy

PS American Literature
3563 Individual Authors -> 1961-2000 -> M
.C337 Author's Cutter number, using the second letter (mCcarthy)
R63 Cutter based on title (“Road” – initial articles like a, an, the are ignored)
2006 Publication Year

Multiple Volumes or Parts

Works with multiple volumes will have a final line representing the volume or part number. "Volume" and "Part" will typically be abbreviated "V." and "Pt.", respectively.

Example of a multiple volume call number

Title: Everyone in Dickens
Author: George Newlin

PR English Literature
4589 19th century, 1770/1800-1890-1900 -> Individual Authors -> Dickens, Charles
.N48 Cutter based on author ("Newlin")
1995 Publication Year
V.1 Volume


Call Numbers at Cowles

Here is where you'll find books by call number in Cowles Library:

A - L 2nd Floor, East
M - Z Lower Level, East


LC Classification

A             General Works

B             Philosophy. Psychology. Religion.

C             Auxiliary Sciences of History

D             History (except America)

E              History: America

F              History: America

G             Geography. Anthroplogy. Recreation.

H             Social Sciences

J              Political Science

K             Law

L              Education

M            Music

N             Fine Arts

P             Language and Literature

Q             Science

R             Medicine

S              Agriculture

T              Technology (General)

U             Military Science

V             Naval Science

Z              Bibliography. Library Science. Information Resources (General)

For a much more detailed outline, visit