Section, Pub. L. 87–195, pt. II, §525, formerly §§503(e), 509(b), as added Pub. L. 88–633, pt. II, §201(a), (d), Oct. 7, 1964, 78 Stat. 1011; amended Pub. L. 89–171, pt. II, §201(f), Sept. 6, 1965, 79 Stat. 657; renumbered §525 and amended Pub. L. 90–137, pt. II, §201(b)(3), (i)(2), Nov. 14, 1967, 81 Stat. 455, 457, provided for guaranties until June 30, 1968. See section 2764 of this title.