1. Alkeryd , M. 2006 Evaluation of position sensing techniques for an unmanned aerial vehicle
2. Three-axes attitude determination of spacecraft using a laser;Aruga;IEEE Transactions on Aerospace and Electronic Systems,1977
3. Variability in surface atmospheric electric field measurements;Bennett;Journal of Physics: Conference Series,2008
4. Bishop , G. 1984 Self-tracker: A smart optical sensor on silicon
5. Conte , G. Doherty , P. 2011 A visual navigation system for uas based on geo-referenced imagery