Quadratic systems with a unique finite rest point
The authors study phase portraits of plane quadratic systems \(\dot xP_ 2(x,y),\quad \dot y=Q_ 2(x,y)\) having a unique finite rest point. They show that there exist 111 possible phase portraits without limit cycles and that there are 13 portraits with exactly one limit cycle. In two cases they cannot determine the topological type of the system.
scientific article; zbMATH DE number 4103491