Drug addict treatment and rehabilitation act of 1972 : hearings before the Subcommittee on Alcoholism and Narcotics of the Committee on Labor and Public Welfare, United States Senate, Ninety-second Congress, second session, on S. 2840, a bill to amend the Public Health Service Act so as to authorize emergency assistance for states and nonprofit private agencies in the establishment of centers for maintenance, treatment, and rehabilitation of drug addicts, May 23 and 24, 1972.