. 518 F.2d 899 (6th Cir.). cert. denied, 423 U.S. 930, 96 S. Ct. 280, 46 L. Ed. 2d 258 (1975); members of a group advocating an urpopular position, Puentes v. Sullivan. 425 F. Supp. 249 (W.D.Tex.1977); laborers who are not members of a union, Scott v. Moore, 461 F. Supp. 224 (E.D.Tex.1978): members of t