1 U.S. Code § 103
1 U.S. Code § 103 is about Enacting or resolving words after first section. It is under Chapter 2 (Acts and Resolutions; Formalities of Enactment; Repeals; Sealing of Instruments) of Title 1 (General Provisions) of the Code.
No enacting or resolving words shall be used in any section of an Act or resolution of Congress except in the first.