Statistical and Criticality Analysis of the Lower Ionosphere Prior to the 30 October 2020 Samos (Greece) Earthquake (M6.9), Based on VLF Electromagnetic Propagation Data as Recorded by a New VLF/LF Receiver Installed in Athens (Greece). - Dimitrios Z. Politis; Stelios M. Potirakis; Yiannis F. Contoyiannis; Sagardweep Biswas; Sudipta Sasmal; Masashi Hayakawa (Entropy, 2021)