  We describe an algebraic algorithm which allows to express every one-loop
lattice integral with gluon or Wilson-fermion propagators in terms of a small
number of basic constants which can be computed with arbitrary high precision.
Although the presentation is restricted to four dimensions the technique can be
generalized to every space dimension. We also give a method to express the
lattice free propagator for Wilson fermions in coordinate space as a linear
function of its values in eight points near the origin. This is an essential
step in order to apply the recent methods of L\" uscher and Weisz to
higher-loop integrals with fermions.
