McCann, R. C. A classification of centers. (English) Zbl 0179.13101 Pac. J. Math. 30, 733-746 (1969). Page: −5 −4 −3 −2 −1 ±0 +1 +2 +3 +4 +5 Show Scanned Page Cited in 1 Document Keywords:ordinary differential equations PDF BibTeX XML Cite \textit{R. C. McCann}, Pac. J. Math. 30, 733--746 (1969; Zbl 0179.13101) Full Text: DOI