Established between 1895 and 1903, the Superintendent of Documents classification system, called SuDoc for short, is based on the current organization of the Federal Government. Classification is by government author, or agency. For example, A=Agriculture Dept., HE=Health and Human Services Dept. Because of changes in the organizational structure of the Federal Government, call numbers are affected. Publications of a particular agency may be located in several different places in the system.
|I 16.||Education Bureau||1867-1929|
|FS 5.||Education Office||1939-1969|
|HE 5.||Education Office||1970-1972|
|HE 19.||Education Office||1972-1979|
If you have located a publication under its current number, the online database will list any previous classification numbers, and the dates during which those numbers were active.
LEVELS OF CLASSIFICATION
C = Department of Commerce (government department or agency)
C 3. = Census Bureau (the agency or subordinate office)
C 3.2: = General Publications (series, serial title, or category of publication)
Letters and numbers up to the colon = class stem
C 3.2:C 24/9 (letters and numbers after the colon = the individual publication)
For further detail, consult: MacGilvray, M. (Ed.). (1993). GPO classification: A practical guide to the Superintendent of documents classification system. Revised January 1993. Washington, DC: U.S. Government Printing Office. [GP 3.29:P 88/993]