The very short supersoft X-ray state of the classical nova M31N 2007-11a M. Henze, W. Pietsch, G. Sala, M. Della Valle, M. Hernanz, J. Greiner, V. Burwitz, M. J. Freyberg, F. Haberl, D. H. Hartmann et al. (2 more) A&A, 498 2 (2009) L13-L16 Published online: 01 April 2009 DOI: 10.1051/0004-6361/200811581