discussed Cited "see, e.g." Roland Buzenius v. National Labor Relations Board Id.; see also Abrams v. Communications Workers, 59 F.3d 1373, 1378-79 (D.C.Cir.1995) (applying IUE without discussion). 15 Similarly, in Nielsen v. International Ass'n of Machinists & Aerospace Workers, 94 F.3d 1107 (7th Cir.1996), cert. denied, 520 U.S. 1165 , 117 S.Ct. 1426 , 137 L.Ed.2d 536 (1997), the Seventh Circuit held that a union-security clause stating that "[a]s a condition of continued employment, all employees ... shall either become a member of the Union and pay dues thereto, or ... shall pay an amount equal to the Union's initiation fee and ... the regular monthly dues and fees …