Elementos de la mathematica : escritos, para la utilidad de los principiantes /

T.1: [32], 213 p., [3] en bl. -- T.2: [12], 321, [3] en bl., [16] h. pleg. -- T.3: [20], 305 p., [3] en bl., 3 h. pleg., 6 h. pleg.

Clean Air Act amendments of 1987 : hearings before the Subcommittee on Environmental Protection of the Committee on Environment and Public Works, United States Senate, One hundredth Congress, first session, on S. 300, S. 321, S. 1351, and S. 1384.

"June 19; July 22 and 23, 1987"--Pt. 2.