Bautin Nikolai Nikolaevich

Publications in Math-Net.Ru

1. Estimation of the number of algebraic limit cycles of the system $\dot x=P(x,\,y)$, $\dot y=Q(x,\,y)$ with algebraic right-hand sides
   
   Differ. Uravn., 16:2 (1980),  362
2. On the number of limit cycles appearing with variation of the coefficients from an equilibrium state of the type of a focus or a center
   
   Mat. Sb. (N.S.), 30(72):1 (1952),  181–196


3. Письмо в редакцию
   
   Differ. Uravn., 2:3 (1966),  436