Section text and notes
Pub. L. 94–163, title I, § 10289 Stat. 876 Pub. L. 94–385, title I, § 16490 Stat. 1142 Pub. L. 95–619, title VI, § 691(b)(2)92 Stat. 3288 Pub. L. 95–620, title VIII, § 80292 Stat. 3347 Section, , , ; , , ; , , ; , , , provided for incentives to develop underground coal mines.