1. Banks, P. M., , G., Kockarts, , Aeronomy, part B, chap. 15.4 Academic, San Diego, Calif., 1973,
2. In situ studies of turbulence in the middle atmosphere by means of electrostatic ion probes;Blix,1988
3. Fourier transforms and their physical applications;Champeney,1973
4. Chapman, S., , T. G., Cowling, , The Mathematical Theory of Non-Uniform Gases, 3rd ed. chap. 14 Cambridge University Press, New York, 1970,
5. Lower thermosphere densities of N2, O, and Ar under high latitude winter conditions;Dickinson;J. Atmos. Terr. Phys.,1985