  We relate the analytic spread of a module expressed as the direct sum of two
submodules with the analytic spread of its components. We also study a class of
submodules whose integral closure can be obtained by means of a simple computer
algebra procedure once the integral closure of each row ideal is known. In
particular, we analyze a class of modules, not necessarily of maximal rank,
whose integral closure is determined by the family of Newton polyhedra of their
row ideals.
