Influence of pore-scale disorder on viscous fingering during drainage R. Toussaint, G. Løvoll, Y. Méheust, K. J. Måløy and J. Schmittbuhl Europhys. Lett., 71 4 (2005) 583-589 Published online: 22 July 2005 DOI: 10.1209/epl/i2005-10136-9