1. Computer and Information Science, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
2. Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
3. Georgia Institute of Technology, Atlanta, Georgia, United States of America
4. University of Pennsylvania, Philadelphia, Pennsylvania, USA
5. SRI International, Menlo Park, California, United States of America
6. SRI International, Menlo Park, California, USA
7. University of Pennsylvania, Philadelphia, USA