00317nam a2200121Ia 4500082002500000100001700025245006100042260003400103300002200137490002600159500000500185700000500190  a519.5024574bOk41.DE  aOkubo, Akira  aDiffusion and ecological problems; mathematical modelsb  aBerlinbSpringer-Verlagc1980  axiii, 254p. Index  aBiomathematicsv v.10  a  a