Li, Keqiang Generalization of results on the existence of periodic solutions of convex Hamiltonian systems by using the Ekeland index theory. (Chinese. English summary) Zbl 1240.34213 J. Nanjing Norm. Univ., Nat. Sci. Ed. 34, No. 1, 12-18 (2011). MSC: 34C25 37J45 58E50 PDFBibTeX XMLCite \textit{K. Li}, J. Nanjing Norm. Univ., Nat. Sci. Ed. 34, No. 1, 12--18 (2011; Zbl 1240.34213)
He, Mei Invariant groups and invariant solutions of equation \(u_{xx}+u_{yy}+\lambda u^p=0\) on jet bundle \(\mathbb{R}^3\). (Chinese. English summary) Zbl 1212.58006 J. Nanjing Norm. Univ., Nat. Sci. Ed. 32, No. 1, 35-38 (2009). MSC: 58D19 58J70 35A30 PDFBibTeX XMLCite \textit{M. He}, J. Nanjing Norm. Univ., Nat. Sci. Ed. 32, No. 1, 35--38 (2009; Zbl 1212.58006)