1. Internet, http://www.ee.surrey.ac.uk/Personal/L.Wood/constellations/, 1998.
2. Forward, R. L., Hoyt, R. P. and Uphoff, C., The terminator tether: a near-term commercial application of the NASA/MSFC ProSEDS experiment. Proceedings of Tether Technology Interchange Meeting, September 9–10, 1997, NASA/CP-1998-206900, January 1998, p. 109.
3. Vannaroni, G., Dobrowolny, M., Lebreton, J. P., Melchioni, E., De Venuto, F., Harvey, C. C., Iess, L., Guidoni, U., Bonifazi, C. and Mariani, F., Current–voltage characteristic of the TSS-1R satellite: comparison with isotropic and anisotropic models. Geophysics Research Letters 1998, 25, 749.
4. Vannaroni, G., Guidoni, U., Giovi, R. and De Venuto, F., Laboratory investigation of the plasma contacting process in the ionosphere. Report IFSI-CNR, IFSI-90-32, October 1990.
5. Vannaroni, G., Dobrowolny, M., Melchioni, E., De Venuto, F. and Giovi, R., Characterization of the interaction between a hollow cathode source and an ambient plasma. Journal of Applied Physics 1992, 71, 4709.