@article{Kudryavtsev2018an,
author={Kudryavtsev, N.G. and Kudin, D.V. and Uchaikin, E.O.},
title={An approach to finding an integral characteristic of ionospheric and lightning activity from WWLLN observational data},
journal={Russian Journal of Earth Sciences},
publisher={Geophysical Center of the Russian Academy of Sciences},
year={2018},
pages={1-8},
volume={18},
issue={6},
}