“…They give estimates for variations of the local f parameter of the SRS, observed at "Hylaty" in 2001-2003, of approximately 0.4-0.8 Hz, depending on the hour, and the season (higher values in September, October than in August). This is in agreement with the results of other observations at middle latitudes (Belyaev et al, 1990(Belyaev et al, , 1997, especially the observations in Karimshino, at the site of similar L-shell: L 2 (Molchanov et al, 2004).…”