00308nam a2200121Ia 4500082002000000100002400020245006100044260003400105300002000139490001700159500000500176700000500181  a515.35bV515.ND  aVerhulst, Ferdinand  aNonlinear differential equations and dynamical systemsb  aBerlinbSpringer-Verlagc1990  aix, 277p. Index  aUniversitext  a  a