1. Bendat, J. S., , A. G., Piersol, , Random Data: Analysis and Measurement Procedures, John Wiley, New York, 1971,
2. Blackman, R. B., , J. W., Tukey, , The Measurement of Power Spectra, Dover, New York, 1958,
3. Interplanetary flow systems associated with cosmic ray modulation in 1977–1980;Burlaga;J. Geophys. Res.,1984
4. The interactions of energetic particles with the solar wind;Fisk,1979
5. Solar modulation of galactic cosmic rays;Fisk,1980