A new X-ray-selected sample of very extended galaxy groups from the ROSAT All-Sky Survey Weiwei Xu, Miriam E. Ramos-Ceja, Florian Pacaud, Thomas H. Reiprich and Thomas Erben A&A, 619 (2018) A162 Published online: 20 November 2018 DOI: 10.1051/0004-6361/201833062