Zoltán Nagy Michael Flückiger Olgaç Ergeneman Salvador Pane Martin Probst Bradley J. Nelson A wireless acoustic emitter for passive localization in liquids. 2593-2598 2009 ICRA http://dx.doi.org/10.1109/ROBOT.2009.5152292 conf/icra/2009 db/conf/icra/icra2009.html#NagyFEPPN09