RX J1821.6+6827: A cool cluster at z = 0.81 from the ROSAT NEP surveyI. M. Gioia, A. Wolter, C. R. Mullis, J. P. Henry, H. Böhringer and U. G. BrielA&A, 428 3 (2004) 867-875DOI: https://doi.org/10.1051/0004-6361:20041426
