While the vast majority of government publications in the Library are in compact shelving on Level 1 and are arranged according to the Superintendent of Documents (SuDoc) classification system, certain titles are separated out from the regular collection for greater ease of access. The dicennial census (GOV-CENSUS), the Congressional Record (GOV-CONREC), and the United States Code (GOV-USCODE), are also in the compact shelving on Level 1, but are placed before the items with regular SuDoc numbers.

The Superintendent of Documents Classification System
Under this system, all documents published by a particular agency are classed together. The SuDoc numbers are combinations of letters and numbers that reflect the department, the agency and the title of the publication.

For example, in the number C 3.134:993, C = the Commerce Department, 3 = the Census Bureau, 134 = the publication entitled Statistical Abstract, and 993 = the date 1993.

Documents are shelved alphabetically by letter and then numerically:
A 1.1:
A 1.2:
C 1.1:
C 3.2:

All numbers are considered whole numbers, not decimals:
HE 3.2:
HE 3.11:
HE 3.21:

One unfortunate aspect of the SuDoc system is that publications in a series are often scattered throughout the collection because changes in government departments and agencies have resulted in changes in classification numbers. These changes are noted on the shelves.

Congressional Publications
Congressional publications begin with the letter Y, and they are slightly different from the other SuDoc numbers.

Y1's are House and Senate documents and reports, which comprise the Serial Set (i.e., bound volumes of House and Senate documents and reports that are numbered consecutively). The Library holds a nearly complete run of the Serial Set up through the 95th Congress(1977-78), which comes after the items with regular SuDoc numbers on Level 1. From the 96th (1979-80) Congress on, they are available in the Documents microfiche collection on Level 1, arranged by SuDoc number. Only the most current Congresses are available in paper format and these are located in Documents Reference on Level 2.

Y3's are congressional commission publications, and Y4's are congressional committee publications. The number that follows Y3. or Y4. but comes before the colon is a CUTTER NUMBER, composed of letters and numbers taken from important words in the commission or committee names.

The Cutter number is often followed by a slash(/) and then another number. The number that immediately follows the slash is called a raised number, because when the SuDoc number is written out by hand, the raised number is written in superscript. Note that the only number that is raised is the number immediately after a slash -- the next number set reverts to normal. For example, in the number Y4. AP6/1: D36/2, the number 1 after AP6 is raised, D36 is not raised, and the number 2 after D36 is also raised. However, if a raised number is joined by a dash or hyphen to another number, both numbers are raised. For example, in the number Y4. J89/2-11: 979, the numbers 2-11 are raised. Finally, if a raised number is itself followed by a slash, the number after the second slash is raised to an even higher degree than the initial raised number.

Y3. and Y4. numbers are shelved alphabetically and then numerically by Cutter number. If a raised number follows the Cutter number, then raised numbers with no dash precede the same raised number that is followed by a dash and another number. For example, Y4. J89/1: comes before Y4. J89/1-5: which comes before Y4. J89/2:.

Here is a list of congressional publications in correct order:
Y4. F49: 96-89
Y4. F76/1: 94-36
Y4. J89/1: 98-100
Y4. J89/1-12: 984
Y4. J89/2: 98-23
Y4. J89/2: 99-10
Y4. J89/2-10: 984
Y4. J89/2-11: 979

What follows the colon identifies the individual published piece. This identification could be in the form of a date, a number or numbers, or a Cutter number (letters plus numbers). To determine the order of the publications, follow the rule dates before numbers before letters (Do Not Lie). If a Cutter number follows the colon, the Cutter number is often followed by a raised number or a series of raised numbers. Raised dates are shelved before raised numbers. For example:
Y4. AP6/1: D36
Y4. AP6/1: D36/950
Y4. AP6/1: D36/951
Y4. AP6/1: D36/2