499 U.S. 606 499 U.S. 606 111 S.Ct. 1539 113 L.Ed.2d 675 AMERICAN HOSPITAL ASSOCIATION, Petitioner,v.NATIONAL LABOR RELATIONS BOARD et al. No. 90-97. Argued Feb. 25, 1991. Decided April 23, 1991. Syllabus The National Labor Relations Board has promulgated a rule providing that, with exceptions for, inter alia, cases presenting “extraordinary circumstances,” eight, and only […]