Examples of the radial-velocity fitting for the white dwarfs 0209−0140 (top panels) and 0807−3622 (bottom panels), respectively of T_eff ≈ 9500 K and T_eff ≈ 17 000 K. The red-dashed curves represent the model-fit without the additional Gaussian functions, which are included in the blue-solid curves. The shaded region in the Gaussian fit panels represent 50 random draws of the best-fit distributions.