H.R. 39, to require the Secretary of the Interior to establish a program to provide assistance in the conservation of neotropical migratory birds : hearing before the Subcommittee on Fisheries Conservation, Wildlife, and Oceans of the Committee on Resources, House of Representatives, One Hundred Sixth Congress, first session, February 11, 1999, Washington, DC. (U.S. G.P.O. :, 1999)