The concentration–mass relation of clusters of galaxies from the OmegaWINGS surveyA. Biviano, A. Moretti, A. Paccagnella, B. M. Poggianti, D. Bettoni, M. Gullieuszik, B. Vulcani, G. Fasano, M. D’Onofrio, J. Fritz and A. CavaA&A, 607 (2017) A81DOI: https://doi.org/10.1051/0004-6361/201731289