Zhang, Zhifen About singular points of a polynomial system. (English) Zbl 0651.34024 Boll. Unione Mat. Ital., VI. Ser., C, Anal. Funz. Appl. 5, 367-382 (1986). This paper classifies orbits of a two-dimensional autonomous system of ordinary differential equations, in the neighborhood of a degenerate critical point, with assumptions on the linear terms. Reviewer: Michael Sever (Jerusalem) MSC: 34C05 Topological structure of integral curves, singular points, limit cycles of ordinary differential equations Keywords:two-dimensional autonomous system; degenerate critical point PDFBibTeX XMLCite \textit{Z. Zhang}, Boll. Unione Mat. Ital., VI. Ser., C, Anal. Funz. Appl. 5, 367--382 (1986; Zbl 0651.34024)