Online Material

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Figure 2:

Wide field DSS-2-infrared survey image of the G61.48+0.09 star-forming region. The squares represent the observed target a) and control b) fields of view.

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Figure 3:

2MASS CMD of the target field. The stars used for the photometric calibration are marked with open circles.

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Figure 4:

Photometric calibration in the J-, H-, and $K_{\rm S}$ -bands for the G61.48+0.09 field. Left panels show the photometric calibration from instrumental (INSTR) to the calibrated magnitudes (2MASS). Central panels show the difference between the calibrated photometry and the 2MASS photometry. Right panels show the PSF fitting $\sigma$ parameter provided by ALLFRAME.