1. Durand and Caseau, Disponibilité du système GPS—Partie 2. Navigation No. 153, January 1991.
2. Thiebolt, V., Zwolska, F. and Lansard, E., Optimisation of a navigation constellation design based on operational availability constraint. GNSS’98, Toulouse, December 1998.
3. Thiebolt, V., Zwolska, F., Deguine, B. and Lansard, E., Operational constellation design for navigation needs: a multicriteria approach. IAF’98, Melbourne, September 28–October 2, 1998.
4. Walker, J. G., Continuous whole-Earth coverage by circular-orbit satellites patterns. Royal Aircraft Est. Technical Report 77044, March 1977.
5. Lansard, E. and Palmade, J. -L., Satellite constellation design: Searching for global cost-efficiency trade-offs. Workshop IAF, 17–19, November 1997.