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Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Images of samples after a lightning strike and ultrasonic tests for (a) L_ref, (b) L_TP and (c) L_ECF, where C-Scan (top) and B-Scan (bottom) visualization.