Multi-wavelength observations for source G25.71: (a) left: three-color image of 4.5 μm (blue), 8.0 μm (green), and 24 μm (red); (right) 870 μm contours overlaid on a 70 μm color scale. The 870 μm contour levels start at 5.3σ in steps of 7σ (σ = 61 MJy beam⁻¹). (b) 850 μm contours overlaid on a 450 μm color scale. The 850 μm contour levels start at 6σ in steps of 8σ (σ = 83 MJy beam⁻¹). (c) 3.5 mm contours overlaid on a 1.3 cm color scale. For CD configuration observations. (d) 3.5 mm contour levels start at −3σ, 3σ in steps of 8σ (σ = 0.26 MJy beam⁻¹). (e) 1.3 mm contour levels start at −3σ, 3σ in steps of 4σ (σ = 1.34 MJy beam⁻¹). For BCD configuration observations. (f) 3.5 mm contour levels are −3σ, 3σ, 7σ, 13σ, 20σ, and to maximum in steps of 13σ (σ = 0.16 MJy beam⁻¹). (g) 1.3 mm contour levels are −3σ, 3σ, 5σ, 10σ and to maximum in steps of 8σ (σ = 0.66 MJy beam⁻¹) superimposed on a 24 μm color scale. The ellipses with numbers indicate the positions of extracted sources. The crosses in the 1.3 mm (B)CD configuration observations indicate the peak positions of the corresponding cores and condensations in the 3.5 mm (B)CD configuration observations. The dashed and dotted circles in each subfigure indicate the primary beam scales of 3.5 and 1.3 mm PdBI tracks, respectively. The blue triangle indicates the position of 6668 MHz methanol masers.