How to Read SuDoc Numbers for Federal Documents

Federal Documents use different call numbers than other materials in Dudley Knox Library.

SuDoc (Superintendent of Documents) classification numbers organize documents by the United States government agency that produced them, not by their subject. The letter at the beginning of the call number signals the agency name. Although there are exceptions, A call numbers are publications of the Department of Agriculture, C is Commerce, D is Defense, and so on.

Important: This is not a decimal system. The number after the dot is a whole number.

A SuDoc number that begins..

Some agencies you will find in Knox Library's Federal Docs collection:

We always welcome your questions! Please see Library Staff for help.