27 C.F.R. § 28.91
Sec. 309, Tariff Act of 1930, 46 Stat. 690, as amended ( 19 U.S.C. 1309 ); sec. 3, Act of June 18, 1934, 48 Stat. 999, as amended ( 19 U.S.C. 81c ); sec. 201, Pub. L. 85-859, 72 Stat. 1362, as amended ( 26 U.S.C. 5214 ); sec. 3, Pub. L. 91-659, 84 Stat. 1965, as amended ( 26 U.S.C. 5066 )