  We perform the sewing of two (dual) Ramond reggeon vertices and derive an
algorithm by means of which the so obtained four-Ramond reggeon vertex may be
explicitly computed at arbitrary oscillator (mass) level. A closed form of the
four-vertex is then deduced on the basis of a comparison to all terms obtained
by sewing that contain only level zero and one oscillators. Results are
presented for both complex fermions and for the previously studied case of real
fermions.
