19 U.S.C. § 1752
Any article imported or brought into the United States—
may, without payment of any duty or internal-revenue tax, be entered under bond under this section for the purpose of exhibition at a fair, or for use in constructing, installing, or maintaining foreign exhibits at a fair.
(Pub. L. 86–14, § 3, , 73 Stat. 18.)
Presidential determination of cultural significance of objects and exhibition or display thereof in the national interest, see section 2459 of Title 22, Foreign Relations and Intercourse.