No. 21056. Argued March 11, 1968. Decided February 11, 1969. Mr. Frank J. Donner, New York City, of the bar of the Court of Appeals of New York, pro hac vice, by special leave of court, with whom Mr. David Rein, Washington, D.C., was on the brief, for petitioner. Mr. John D. Burgoyne, Atty., National Labor Relations Board, with whom Messrs. Arnold Ordman, General Counsel, Dominick L. Manoli, Associate General Counsel, Marcel Mallet-Prevost, Asst. General Counsel, and Mrs. Nancy M. Sherman, Atty.