  Using Random Matrix Theory we set out to compute the microscopic correlators
of the Euclidean Dirac operator in four dimensions. In particular we consider:
the chiral Orthogonal Ensemble (chOE), corresponding to a Yang-Mills theory
with two colors and fermions in the fundamental representation, and the chiral
Symplectic Ensemble (chSE), corresponding to any number of colors and fermions
in the adjoint representation. In both cases we deal with an arbitrary number
of massive fermions. We use a recent method proposed by H. Widom for deriving
closed formulas for the scalar kernels from which all spectral correlation
functions of the chGOE and chGSE can be determined. Moreover, we obtain
complete analytic expressions of such correlators in the double microscopic
limit, extending previously known results of four-dimensional QCD at beta=1 and
beta=4 to the general case with N_f flavors, with arbitrary quark masses and
arbitrary topological charge.
