Sanders, J. A. and Verhulst, F. <br/><br/>
Averaging methods in nonlinear dynamical systems   

 - New York  Springer-Verlag  1985 
 - x, 247p. Index 
 - Applied Mathematical Sciences    v. 59 .
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<br/><br/><label>Dewey Class. No.: </label>515.35  / Sa215.AM