The government publications collection is shelved by SUDOC
(Superintendent of Documents) classification number. The basis of this
system is to group together Government Publications by author, author
meaning the department, commission, or agency that issued the publication.
It is an alphanumeric system.
Therefore, information produced by the Department of Agriculture is found
in the A's, Health and Human Services Department in HE and Congressional
hearings will be found in the Y4s.
Here is an example of a SuDoc number:
The class number, before
the colon, denotes the agency (Dept. of Commerce), subagency (3=Census),
and the series (186). The report number indicates a unique publication
within the series, and may consist of numbers or letters and numbers
with punctuation. Punctuation includes colons, periods, slashes
and dashes, all of which separate segments of the call number.
A more thorough introduction to SuDocs numbers can be found in
of the Superintendent of Documents Classification System.