Tracing low-mass galaxy clusters using radio relics: the discovery of Abell 3527-bis F. de Gasperin, H. T. Intema, J. Ridl, M. Salvato, R. van Weeren, A. Bonafede, J. Greiner, R. Cassano and M. Brüggen A&A, 597 (2017) A15 Published online: 19 December 2016 DOI: 10.1051/0004-6361/201628945