00388    a2200097   4500082001500000100002100015245011400036260005000150300003600200650005400236  a333.91 DAV  aDavis, Robert K.  aThe Range of Choice in Water Management : a study of dissolved oxygen in the potomac estuarycRobert K. Davis  aWashington :bResources for the Future,c1968  axviii, 196p. :bill ., ;c23 cm  aWater Quality Management -- Potomac River Estuary