Index Theory and Morse Sturm systems
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Hu, Xijun; Portaluri, Alessandro Index theory for heteroclinic orbits of Hamiltonian systems. Calc. Var. Partial Differential Equations 56 (2017), no. 6, Art. 167, 24 pp.
Portaluri, Alessandro; Waterstraat, Nils Yet another proof of the Morse index theorem. Expo. Math. 33 (2015), no. 3, 378–386.
Capietto, Anna; Dalbono, Francesca; Portaluri, Alessandro A multiplicity result for a class of strongly indefinite asymptotically linear second order systems. Nonlinear Anal. 72 (2010), no. 6, 2874–2890.
Portaluri, Alessandro On a generalized Sturm theorem. Adv. Nonlinear Stud. 10 (2010), no. 1, 219–230.
Portaluri, A. Indefinite Sturm theory. (Russian) Funktsional. Anal. i Prilozhen. 43 (2009), no. 4, 91–96; translation in Funct. Anal. Appl. 43 (2009), no. 4, 316–319
Portaluri, Alessandro Maslov index for Hamiltonian systems. Electron. J. Differential Equations 2008, No. 09, 10 pp.
Portaluri, Alessandro; Waterstraat, Nils Corrigendum to "A Morse-Smale index theorem for indefinite elliptic systems and bifurcation'' [J. Differential Equations 258 (5) (2015) 1715–1748] [MR3295598]. J. Differential Equations 264 (2018), no. 4, 3067–3069.
Portaluri, Alessandro; Waterstraat, Nils A Morse-Smale index theorem for indefinite elliptic systems and bifurcation. J. Differential Equations 258 (2015), no. 5, 1715–1748.
Dalbono, Francesca; Portaluri, Alessandro Morse-Smale index theorems for elliptic boundary deformation problems. J. Differential Equations 253 (2012), no. 2, 463–480.