Azevedo, M. B.; Cesar, S. B. G.; Coutinho, J. A.; Faccini, J. L. H.; Freitas, S. C.; Vinhas, P. A. M.; Jian, S. Characterization of Velocity and Shape of Rising Bubbles in a Stagnant Liquid Vertical Column by Ultrasonic and Visualization Techniques. ien prog rep 2015, 17.