Digitised Sky Surveys (DSS), 2MASS, and WISE finding charts (90   ×   90 arcsec², north is up, east to the left) for WISE J0521+1025. The red open circle marks the position of the target at the WISE epoch (i.e. the centre of each image). The red arrows mark the bright WISE source and the correct counterparts in 2MASS and DSS (if detected) of the HPM object. In this particular case, we see an overlapping background object in both 2MASS and DSS (within the open circle), whereas the correct counterpart is only seen in 2MASS as the brighter object north of the background object. Compared to the other finding charts (Figs. 2 and 3), a higher magnification was chosen to better show the source confusion in this case.