Andres, Jan On a possible modification of Levinson’s operator. (English) Zbl 0626.34037 Nonlinear oscillations, Proc. 11th Int. Conf., Budapest 1987, 345-348 (1987). For the entire collection see Zbl 0624.00010. Cited in 2 Documents MSC: 34C20 Transformation and reduction of ordinary differential equations and systems, normal forms Keywords:second order differential equations Citations:Zbl 0624.00010 PDF BibTeX XML