Nomenclature and description of Electro-Luminescence (EL) observations: cell cracks and other observationsBengt Jaeckel, Matthias Pander, Paul Schenk, Aswin Linsenmeyer and Jochen KirchEPJ Photovolt., 15 (2024) 44DOI: https://doi.org/10.1051/epjpv/2024039