Nos. 79-1807, 79-1883. Argued May 23, 1980. Decided October 30, 1980. John Regis Valaw, James J. Flaherty (argued), Pittsburgh, Pa., Stephen J. Cabot, Pechner, Dorfman, Wolffe, Rounick Cabot, Philadelphia, Pa., for United Dairy Farmers Cooperative Association. Hugh J. Beins, Jonathan G. Axelrod (argued), Bethesda, Md., Louis B. Kushner, Rothman, Gordon, Foreman, Groudine, P. A., Pittsburgh, Pa., for Teamsters Local Union No. 205. Richard B. Bader (argued), Atty., William A. Lubbers, Gen. Counsel