Rapid variability of accretion in AM HerculisD. de Martino, G. Matt, B. T. Gänsicke, R. Silvotti, J. M. Bonnet-Bidaud and M. MouchetA&A, 396 1 (2002) 213-217DOI: https://doi.org/10.1051/0004-6361:20021405