Planar dynamical systems : selected classical problems This book presents in an elementary way the recent significant developments in the qualitative theory of planar dynamical systems. The subjects are covered as follows: the studies of center and isochronous center problems multiple Hopf bifurcations and local and global bifurcations of the equivariant planar vector fields which concern with Hilberts 16th problem. This book is intended for graduate students post doctors and researchers in the area of theories and applications of dynamical systems. For all engineers who are interested the theory of dynamical systems it is also a reasona