# Topics

Among other topics, we highlight the following ones:

• Formal and analytic solutions for ordinary differential equations in the complex domain. Stokes multipliers.
• Formal and analytic solutions of other kinds of functional equations: difference, q-difference, differential-difference, moment-differential and PD equations.
• Summability of WKB solutions, singular perturbations problems.
• Asymptotic expansions, Borel summability.
• Algebraic study of solutions of differential equations and D-modules.