Shevtsov I L

Publications in Math-Net.Ru

1. On the Coppel Problem for Quadratic Systems with a Fine Focus
   
   Differ. Uravn., 41:8 (2005),  1100–1104
2. Normal-Size Limit Cycles of Quadratic Systems with a Structurally Unstable Focus
   
   Differ. Uravn., 40:8 (2004),  1076–1084