Broad-band spectral energy distribution of the afterglow of GRB 071028B including GROND and Swift/XRT data points. Based on the dust model of a starburst (SB), the shaded area represents the extrapolation of the optical and near-infrared data points with the best-fit spectral index of and without dust. Using Minuit, the data points are best fit by a single power law with a spectral index of (dashed line) in combination with the dust model of an SB with an intrinsic extinction of (solid line).