1. A visual odometer for autonomous helicopter flight;Amidi;Robotics and Autonomous Systems,1999
2. P. Campoy, A. Barrientos, P.J. Garcia-Pardo, J. del Cerro, I. Aguirre, An autonomous helicopter guided by computer vision for visual inspection of overhead power cable, in: Proceedings of the Fifth International Conference on Live Maintenance, Madrid, May 2000.
3. P. Doherty, G. Granlund, K. Kuchcinski, E. Sandewall, K. Nordberg, E. Skarman, J. Wiklund, The WITAS unmanned aerial vehicle project, in: Proceedings of the 14th European Conference on Artificial Intelligence, Berlin, August 2000.
4. P.J. Garcia-Pardo, On the properties of a contrast descriptor for aerial imagery, Technical Report IRIS-00-391, Institute for Robotics and Intelligent Systems, University of Southern California, Los Angeles, CA, November 2000.
5. A.E. Johnson, Surface landmark selection and matching in natural terrain, in: Proceedings of the IEEE Computer Vision and Pattern Recognition, Hilton Head Island, SC, June 2000.