Mary Ellen Foster Ellen Gurman Bard Markus Guhe Robin L. Hill Jon Oberlander Alois Knoll The roles of haptic-ostensive referring expressions in cooperative, task-based human-robot dialogue. 295-302 2008 HRI http://doi.acm.org/10.1145/1349822.1349861 conf/hri/2008 db/conf/hri/hri2008.html#FosterBGHOK08