00725naa#a2200205#i#450# EN\\bibl\20508 20260310155009.2 2500-0535 20180331b2018####ek#y0engy0150####ca ENG RU Electron density at F1-layer heights in the last solar minimum (2007–2009) Journal article Irkutsk Institute of Solar-Terrestrial Physics SB RAS 2018 2 с. Journal article local Геология. Геологические и геофизические науки. 55 ENG Kushnarenko Galina Petrovna Yakovleva Olga Evgenyevna Kuznetsova Galina Mihaylovna ras.editorum.ru