In the Thomas Jefferson Library, Superintendent of Documents classification (SuDoc) numbers are used to locate most print government documents. The system is used to shelve the documents by the issuing agency. The organizational structure of the United States Government is followed - that is, subordinate divisions and bureaus are grouped with the parent agency or department. Each parent department is assigned a letter symbol, such as:
A = Agriculture Department
C = Commerce Department
J = Justice Department
Y = Congress
A strict number sequence is used in the SUDOC scheme; they are arranged by whole numbers, not decimals. Example: “J 1.8" will be shelved before “J 1.14"