An elementary proof of the conley โ{128}{148} Zehnder theorem in symplectic geometry -- An "A-Priori" estimate for oscillatory-equations -- On the structure of germs of vector fields in ?3 whose linear part generates rotations -- Fixed point results for symplectic maps related to the arnold - conjecture -- Topological invariants as numbers of translation -- Abelian integrals and global hopf bifurcations -- On the numerical determination of the dimension of an attractor -- Global stability of generic two-parameter families of gradients on three-manifolds