Ambrosetti, A. Functional equations in nonlinear analysis. (Italian) Zbl 1194.39001 Boll. Unione Mat. Ital., Sez. A, Mat. Soc. Cult. (8) 5, No. 3, 393-406 (2002). Cited in 1 Review MSC: 39-02 Research exposition (monographs, survey articles) pertaining to difference and functional equations 47-02 Research exposition (monographs, survey articles) pertaining to operator theory 39Bxx Functional equations and inequalities 47J05 Equations involving nonlinear operators (general) 35B32 Bifurcations in context of PDEs 47J15 Abstract bifurcation theory involving nonlinear operators PDFBibTeX XMLCite \textit{A. Ambrosetti}, Boll. Unione Mat. Ital., Sez. A, Mat. Soc. Cult. (8) 5, No. 3, 393--406 (2002; Zbl 1194.39001)