Merchant seamen : hearings before the Committee on Merchant Marine and Fisheries, House of Representatives, Seventy-seventh Congress, first session, on H.R. 2662, a bill to establish hiring halls under the control of shipping commissioners for the engaging of seamen for certain vessels, to control subversive activities among seamen, to impose additional citizenship requirements for manning vessels of the United States, to establish more stable labor relations in the merchant marine and to protect the status of the American merchant marine as an integral part of the national defense, February 26, 27, 28, March 5, 6, 7, and 11, 1941