Tiwari, Shailendra Kumar, B.S. Satyanarayana, A. Gopalkrishna Pai, and Kunal K. Trivedi. 2009. “Circular Capacitance Micromachined Ultrasonic Transducer”. Defence Science Journal 59 (6), 627-33. https://doi.org/10.14429/dsj.59.1568.