00288nam a2200109 a 450000500170000002000150001708200210003210000150005324500360006826000560010430000180016020251203091038.0  a0582455960  a628.168,bD, mas  aMason C.F.  aBiology of freshwater pollution  aLoNew DelhionbLongman Scientific & Technicalc1988  axi,250p, 22cm