Proceedings of the Royal Society of Edinburgh Section A Mathematics · 1989 · 47 citations · 2 references
Natural SciencesMathematicsDifferential EquationsExistence TheoremsSystems Of Differential Equations
Synopsis In this note we demonstrate that a conjecture about a necessary and sufficient condition for the existence of a centre of cubic equations is not true.
2
W. A. Coppel · Journal of Differential Equations · 1966 · 277 citations