Roussarie, Robert. <br/><br/>
Bifurcations of planar vector fields and Hilbert's sixteenth problem   
by Robert Roussarie 
 - Basel  Birkhauser verlag  1998 
 - xvii, 204p. 
 - Progress in mathematics, Vol.164 .
<br/><br/><label>ISBN: </label>3764359005 
<br/><br/><label>Dewey Class. No.: </label>515.63  / N981