Call Numbers:
The James E. Brooks Library uses the Superintendent of Documents (SuDocs) classification system for all federal government publications. The following make up a SuDoc call number:
Most classification deal with the items content; SuDocs deal with the items authorship, as in the creating Federal agency. For example, call numbers beginning with the letter A are published by the Agriculture Department, C for Commerce, D for Defense, etc. These are not always mnemonic, and there are some two and three letter designation, notably NAS for NASA.
Citing government publications for the most part is like citing any other resource. You first need to determine if it is a monograph (a book) or a serial (ongoing publications). Most style guides will use the same criteria as books and serials. If they do not, then they use the same criteria for legal resources such as the Bluebook style.
There are two published manuals devoted to government publications.
Cornell University has a wonderful website describing how to cite government publications using MLA and APA.
Columbia College in Vancouver, Canada has a terrific overview guide describing in detail how to cite the different forms and formats of government publications: APA 7. Chicago 18. MLA 9.