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Western Colorado's Selective University

SuDocs Classification System

Government Publications at Colorado Mesa University are organized according to the Superintendent of Documents (SuDocs) Classification System in which each individual publication has a unique call number. SuDocs call numbers start with one or two letters which stand for the issuing agency of the publication, unlike the Library of Congress Classification System where the letters stand for a particular subject. Also, they are located on the upper left front cover (not the lower spine) of the print publications and are always printed in linear fashion. Government Publications at Colorado Mesa University are found in the print, CD-ROM, online, and microform collections; there is also a small section of Gov Docs in the Reference stacks.

Typical SuDocs call numbers look like this:

L 2.3/4:998-99

I 3.134/2:/C 83/2/994

The letter or letters beginning the number are simply treated alphabetically (A comes before AE which comes before C, etc.). Again, these are abbreviations for the issuing government agencies.

After the initial letter(s), the following numbers on either side of the period (.) but before the slash (/) or colon (:) are both read as whole numbers. Do NOT treat the second number as a decimal. The following are in correct order, left to right:

J 45.9/2:AG 8 J 45.18/9:F 7 J 45.429:23/985 J 45.4186:46

In SuDoc call numbers, after the initial letters, sections (which are read as a complete unit) are divided by periods (.) or colons (:), which are unique to the SuDocs Classification System. Within a section, there can be divisions separated by slashes (/) or hyphens (-). Read one section at a time in order and usually an item will be easily located on the shelf.

A few things to remember

With all SuDocs call numbers (and even within individual sections), nothing comes before something. For example,

SE 5.9:3 is shelved before SE 5.9:3 SUPP. 1

When a string of numbers is followed by words or abbreviations, the words go in alphabetical order:

C 15.2:R 57/2/978-82/SUPP comes before C 15.2:R 57/2/978-82/UPDATE

When call numbers match up to a punctuation point and letters follow, then items are shelved alphabetically.

View a list of issuing agencies by letter on the website.