Citation: Pm. Fitzpatrick et al., Spectral flow and bifurcation of critical points of strongly indefinite functionals part II. Bifurcation of periodic orbits of hamiltonian systems, J DIFF EQUA, 163(1), 2000, pp. 18-40
Citation: Pm. Fitzpatrick et al., Spectral flow and bifurcation of critical points of strongly-indefinite functionals part I. General theory, J FUNCT ANA, 162(1), 1999, pp. 52-95