Water-quality data-collection activities in Colorado and Ohio.
Hren, Janet.
Childress, Carolyn J. Oblinger.
Washington, D.C. : U.S.G.P.O. ; Alexandria, Va. : For sale by the Distribution Branch, Text Products Section, U.S. Geological Survey,
[1987-
ch. A. Phase 1, inventory and evaluation of 1984 programs and costs / by Janet Hren ... [et al.]. -- ch. B. Phase 2, Evaluation of 1984 field and laboratory quality-assurance practices / by Carolyn J. Oblinger Childress ... [et al.].
Water quality
Water quality