Detected continuum emission at the position of the CO(2–1) emission line for the sample presented in this work. Contours for J1524+4409, J1330+1810, J1633+3134, and J1650+4251 start at ±2σ and increase in intervals of ±1σ, where σ is given in Table 2. Contours are given in steps of ±50σ starting at 50σ for B1608 and in steps of ±100σ starting at 100σ for B1152 and B1600. The red cross indicates the peak position of the gas emission where detected, and the optical emission for the three QSOs not detected in CO(2–1).