Multiwavelength images of the bubble N131 from 3.6 μm to 21 cm. The saturated region within the dashed square is shown in the bottom-left corner of each subfigure, as a zoom in with adjusted intensity scale. The unit of each colour bar is, respectively, MJy sr^-1 for 3.6, 4.5, 5.8, 8.0, 24, 70, 160, 250, 350, 500 μm, Jy beam^-1 for 1.1 mm, and 21 cm. In the 500 μm subfigure, the symbols “■”, letters (A, B, ..., and I), and ellipse indicate the positions of eight IRAS point sources, nine molecular clumps, and the ring-like shell of the bubble, respectively.