Construction differential subsidy bills, hearings before subcommittee, 86th Congress, 2d session on H.R. 9172 and identical bills H.R. 91S3, H.R. 9188, and H.R. 9362, H.R. 10844 (identical bills H.R. 9833 and H.R. 10129), Mar. 2-Apr. 12, 1960.