K. Kühl, and H. Sandmaier. Transducers '89 : proceedings of the 5th International Conference on Solid-State Sensors and Actuators and Eurosensors III, volume 2 of Sensors and actuators. A, Physical, page 142-145. Lausanne, Elsevier Sequoia, (1990)
E. Obermeier, H. Sandmaier, and K. Kühl. An Investigation of micromechanical structures, actuators, and sensors : proceedings, New York, NY, IEEE, (1987)