Wide-band symmetrical analog multiplier IC for coherent optical-fiber receivers operating up to 10 Gb/s. - Hans-Martin Rein; Lothar Schmidt; Klaus Wörner; Wilhelm Pieper (IEEE J. Solid State Circuits, 1991)

Continuously variable gigahertz phase-shifter IC covering more than one frequency decade. - Lothar Schmidt; Hans-Martin Rein (IEEE J. Solid State Circuits, 1992)