00329nam a2200121 a 450000500170000002000180001708200160003510000200005124500490007126000420012030000260016250000190018820251203112029.0  a9780486659541  a515.35bNEM  aNemytskii, V.V.  aQualitative theory of differential equations  aNewYorkbDover Publication,INC.c1989  aviii,531P,c18cm.bPB  aIncludes index