1. Catastrophe Theory for Scientists and Engineers;Gilmore,1981
2. Catastrophe optics: Morphologies of caustics and their diffraction patterns;Berry,1980
3. Theory of Perturbations and Asymptotic Methods;Maslov,1965
4. Asymptotic Approximation in Quantum Mechanics;Maslov,1982
5. Two new asymptotic methods in the theory of wave propagation in inhomogeneous media (review);Kravtsov;Soviet Phys. Acoust.,1968