42 U.S.C. ยง 7407
United States Code, 2018 Edition
Title 42 - THE PUBLIC HEALTH AND WELFARE
CHAPTER 85 - AIR POLLUTION PREVENTION AND CONTROL
SUBCHAPTER I - PROGRAMS AND ACTIVITIES
Part A - Air Quality and Emission Limitations
Sec. 7407 - Air quality control regions
From the U.S. Government Publishing Office,