Nos. 20565, 20613. Argued June 14, 1967. Decided January 23, 1968. Mr. Fred O. Weldon, Jr., Dallas, Tex., with whom Mr. David R. Richards, Dallas, Tex., was on the brief, for petitioner in No. 20,565 and intervenor in No. 20,613. Mr. Herbert S. Thatcher, Washington, D.C., also entered an appearance for petitioner in No. 20,565. Mrs. Nancy M. Sherman, Attorney, National Labor Relations Board, with whom Messrs. Arnold Ordman, General Counsel, Dominick L. Manoli, Associate General Counsel, and Marcel