On matching principles -- Singular perturbations of spectra -- Feed-back control of singularly perturbed heating problems -- Singular perturbation methods in a one-dimensional free boundary problem -- Bifurcation analysis of a non linear free boundary problem from plasma physics -- Asymptotic approximations in magneto-hydrcdynamic singular perturbation problems -- Boundary layers in large scale ocean circulation -- Asymptotic methods for the Volterra-Lotka equations -- Small random perturbations of dynamical systems with applications in population genetics -- The description of jumps between Kepler orbits by boundary layer methods -- The 1:2:1-resonance, its periodic orbits and integrals -- Approximations of higher order resonances with an application to Contopoulos' model problem -- On the asymptotic validity of perturbation methods for hyperbolic differential equations.