Yavor Chapanov (2021). CORRELATION BETWEEN VOLCANIC SULFATE AND SOME SOLAR CYCLES. SGEM International Multidisciplinary Scientific GeoConference EXPO Proceedings; 21st SGEM International Multidisciplinary Scientific GeoConference Proceedings 2021, Science and Technologies in Geology, Exploration And Mining, 443-450. https://doi.org/10.5593/sgem2021/1.1/s05.081