A citation for the Electronic Code of Regulations includes the title, part, section, subpart and the revision year. Some regulations have names that are cited in American Psychological Association style. For example, the CFR citation "21 CFR 310.502 Revised as of April 1, 1997" refers to Title 21, Part 310, Subpart 502 published in 1997.
Cornell University explains the general legal citation for the CFR does not need a date if the regulation cited is currently in effect when the document is written. The revision date is placed in parentheses after the main citation if the regulation is outdated, superseded or revised. Depending on the publication style, include the exact Web address of the source and the date the source was viewed.
APA style dictates a format such as "7 C.F.R. § 319 (2000)," which denotes Title 7, Part 319, revised in 2000. The " §" mark means "section number." For a range of section numbers, APA uses two §§ in a row; for example, "§§ 319-320." Include the name of the regulation in APA Style: "Financial Assistance to Individuals, 45 C.F.R. § 234 (2012)."
The e-CFR may issue changes later if the electronic publication contains errors. In this case, an amendment is cited until the new regulation is published.