01072nam a2200277Ia 450000100060000000300050000600500170001100800410002801000150006902000220008405000210010608200190012724501130014626001580025926300090041730000180042650000600044465000250050465000290052970000330055870000340059170000310062571000510065671000490070771000380075616378BIBL20160527183830.0891027s1990    maua     b    00100 eng    a 89018289   a0631173145c90.000 aTD370b.G56 19900 a363.73/94222000aGlobal freshwater qualityba first assessmentcedited by Michel Meybeck, Deborah V. Chapman, Richard Helmer.0 aCambridge, Mass., U.S.A.bPublished on behalf of the World Health Organization and the United Nations Environment Programme by Blackwell Referencec1990.  a9003  ax, 306 p. cm.  aAt head of title: Global Environment Monitoring System. 0aWater quality2Local 0aWaterxPollution.2Local10aMeybeck, M.q(Michel)2Local10aHelmer, Richardd1943-2Local10aChapman, Deborah V.2Local20aGlobal Environmental Monitoring System.2Local20aUnited Nations Environment Programme.2Local20aWorld Health Organization.2Local