Automorphic forms on GL(2) -- The differential equations satisfied by Whittaker functions -- Jacquet's Whittaker functions -- Fourier expansions of automorphic forms -- Invariants of G?\G -- Ramanujan sums on GL(3) -- Eisenstein series -- The analytic continuation and functional equations satisfied by the L-series associated with an automorphic form -- Hecke operators and L-series -- The Mellin transforms of the Whittaker functions