TY - BOOK AU - Case, Richard B. CN - TD433 .C3 CN - TD433 CY - Denver, Colo. : DA - 1981- ID - 40447 KW - Water KW - Drinking water N1 - Periodic updating anticipated. PB - U.S. Dept. of the Interior, Bureau of Land Management: PB - Available from Denver Service Center, PP - Denver, Colo. : PY - 1981- T1 - Small water purification systems / TI - Small water purification systems / VL - 351 ER -