  We introduce gamma structures on regular hypergeometric D--modules in
dimension 1 as special one--parametric systems of solutions on the compact
subtorus. We note that a balanced gamma product is in the Paley--Wiener class
and show that the monodromy with respect to the gamma structure is expressed
algebraically in terms of the hypergeometric exponents. We compute the
hypergeometric monodromy explicitly in terms of certain diagonal matrices,
Vandermonde matrices and their inverses (or generalizations of those in the
resonant case).

Algebraic Geometry;Classical Analysis and ODEs