Spectral and temporal variations of the isolated neutron star RX J0720.4-3125: new XMM-Newton observationsM. M. Hohle, F. Haberl, J. Vink, R. Turolla, V. Hambaryan, S. Zane, C. P. de Vries and M. MéndezA&A, 498 3 (2009) 811-820DOI: https://doi.org/10.1051/0004-6361/200810812
