1. Ultrasonic Motors: Theory and Applications;Ueha,1993
2. Ultrasonic Motors Technologies and Applications;Zhao,2007
3. Contact mechanics of piezoelectric ultrasonic motors;Wallaschek;Smart Materials and Structures,1998
4. Efficiency of ultrasonic motor using traveling wave;Kurosawa;Journal of the Acoustical Society of Japan,1988
5. Finite-element analysis of the rotor/stator contact in a ring-type ultrasonic motor;Maeno;IEEE Transactions on Ultrasonic Ferroelectrics and Frequency Control,1992