FREE-FIELD REPRESENTATION OF TODA FIELD-THEORIES

We study the following problem: Can a classical sl(n) Toda field theor y be represented by means of free bosonic oscillators through a Drinfe ld-Sokolov construction? We answer affirmatively in the case of a cyli ndrical space-time and for real hyperbolic solutions of the Toda field -equations. We establish in fact a one-to-one correspondence between s uch solutions and the space of free left and right bosonic oscillators with coincident zero modes. We discuss the same problem for real sing ular solutions with nonhyperbolic monodromy.