1. Walker, J. G. Satellite constellations. Journal of the British Interplanetary Society, 1984, 37: 559–572.
2. Ballard, A. H. Rosette constellations of earth satellites. IEEE Transactions on Aerospace and Electronic Systems, 1980, 16(5): 656–673.
3. Rider, L. Optimized polar orbit constellations for redundant earth coverage. Journal of the Astronautical Sciences, 1985, 33(2): 147–161.
4. Adams, W. S., Rider, L. Circular polar constellations providing continuous single or multiple coverage above a specified latitude. Journal of the Astronautical Sciences, 1987, 35(2): 155–192.
5. Draim, J. E. Three-and four-satellite continuouscoverage constellations. Journal of Guidance, Control, and Dynamics, 1985, 8(6): 725–730.