Section, Pub. L. 93–531, § 23, Dec. 22, 1974, 88 Stat. 1722; Pub. L. 96–305, § 9, July 8, 1980, 94 Stat. 933; Pub. L. 100–666, § 4(b), Nov. 16, 1988, 102 Stat. 3930, which authorized the Navajo and Hopi Tribes to exchange lands which are part of their respective reservations and provided for additional relocation benefits in the event of such an exchange, was omitted from the Code as being of special and not general application.