Solovieva, M.; Rozhnoi, A.; Fedun, V.; Schwingenschuh, K.; Hayakawa, M. Ionospheric Perturbations Related to the Earthquake in Vrancea Area on November 22, 2014, As Detected by Electromagnetic VLF/LF Frequency Signals. Ann. Geophys. 2015, 58, A0552.