Capozzi, A.; Fortunato, D.; Salvatore, A. Periodic solutions of Lagrangian systems with bounded potential. (English) Zbl 0664.34053 J. Math. Anal. Appl. 124, 482-494 (1987). Reviewer: J.H.Tian MSC: 34C25 PDFBibTeX XMLCite \textit{A. Capozzi} et al., J. Math. Anal. Appl. 124, 482--494 (1987; Zbl 0664.34053) Full Text: DOI
Benci, V.; Fortunato, D. Discreteness conditions of the spectrum of Schrödinger operators. (English) Zbl 0389.35016 J. Math. Anal. Appl. 64, 695-700 (1978). MSC: 35J10 35P15 PDFBibTeX XMLCite \textit{V. Benci} and \textit{D. Fortunato}, J. Math. Anal. Appl. 64, 695--700 (1978; Zbl 0389.35016) Full Text: DOI