J. Andersen, A. Bene, and R. Penner. (2007)cite arxiv:0710.2651
Comment: 24 pages, 4 figures Theorem 3.6 has been strengthened, and Theorems
8.1 and 8.2 have been added.
R. Aroma, K. Raimond, N. Razmjooy, V. Estrela, and J. Hemanth. Imaging and Sensing for Unmanned Aircraft Systems: Volume 2: Deployment and Applications, Institution of Engineering and Technology, (April 2020)