A double radio relic in the merging galaxy cluster ZwCl 0008.8+5215 R. J. van Weeren, M. Hoeft, H. J. A. Röttgering, M. Brüggen, H. T. Intema and S. van Velzen A&A, 528 (2011) A38 Published online: 24 February 2011 DOI: 10.1051/0004-6361/201016185