A novel approach for high power ultrasonic linear motors
T. Hemsel, M. Mracek, J. Wallaschek, P. Vasiljev, in: Ultrasonics Symposium, 2004 IEEE, 2004, pp. 1161–1164.
LibreCat: /record/9519
DOI: 10.1109/ULTSYM.2004.1417988

Piezoelectric transformers - state of the art and development trends
T. Hemsel, W. Littmann, J. Wallaschek, in: Ultrasonics Symposium, 2002. Proceedings. 2002 IEEE, 2002, pp. 645–648.
LibreCat: /record/8926
DOI: 10.1109/ULTSYM.2002.1193485

State of the art and development trends of ultrasonic linear motors
T. Hemsel, J. Wallaschek, in: Ultrasonics Symposium, 2000 IEEE, 2000, pp. 663–666 vol.1.
LibreCat: /record/8915
DOI: 10.1109/ULTSYM.2000.922635