@article { tung2008, title = {Power density requirement of a 4 {MHz} micro-ultrasonic transducer for sonodynamic therapy (article)}, journal = {Biomedical Microdevices}, volume = {10}, year = {2008}, month = {02/2008}, pages = {89-97}, author = {Siu, Tung and Rohling, Robert and Chiao, Mu} }