Supplemental report to the President by the Emergency Board appointed February 20, 1943 pursuant to the railway labor act and executive orders 9172 and 9299 to investigate an unadjusted dispute between certain carriers, including railroads, the Railway Express Agency, refrigerator car companies, and stockyard companies, and certain of their employees represented by Fifteen Cooperating Railway Labor Organizations, concerning requests for a union-shop agreement and for increases in rates of pay May 29, 1943, Washington