[Committee publication] serial, 93d Congress. 21. Merchant marine miscellaneous, hearings before Subcommittee on Merchant Marine, 93d Congress, 1st session, on H.R. 6187, H.R. 7395, S. 902, H.R. 9450 [and] H.R. 8586, pt. 1, May 24-Sept. 20, 1973.