The citation for a slip law includes its public or private law number, which has two parts: the number of the Congress in which it was enacted, and a sequentially assigned number. For example, Pub. L. No. 108-45 is the 45th law passed during the 108th Congress.
A Statutes at Large citation refers to the volume of Statutes at Large in which the law was published, and the page on which it starts. For example, a law with a Statutes at Large citation of 107 Stat. 25 begins on page 25 of volume 107.
A United States Code citation includes a title number and section number. For example, 26 U.S.C. § 115 refers to section 115 of title 26 of the United States Code. Citations to the United States Code Service (USCS) and the United States Code Annotated (USCA) (commercially-published, annotated versions of the United States Code described on the United States Code page) follow a similar format, e.g., 26 U.S.C.A. § 115 or 26 U.S.C.S. § 115.
Keep in mind that The Bluebook: A Uniform System of Citation (often referred to as "the Bluebook") includes additional requirements when preparing citations to statutes for purposes of court filings and law review and law journal articles. Consult Bluebook Rules B12 and 12 for more information. Additionally, court rules may impose additional or different citation format requirements for filings with a particular court.
The popular names table in the United States Code can be used to look up statutes by popular name to find their slip law, Statutes at Large, and United States Code citations. Similar tables appear in the USCS and USCA, as well as in Shepard’s Acts and Cases by Popular Name and in the United States Code Congressional and Administrative News (USCCAN) bound volumes and supplements. The United States Code citation for a public law is also found in the page margin of the statute when published as a slip law or in Statutes at Large.