Spectra resulting from integrating the ¹²CO J = 1−0 and J = 2−1 emissions in interferometric maps in black solid lines, for the sources specified in the top-right corner. Red dotted lines show the profiles obtained by observing the source center with the 30 m telescope. For IRAS 21282+5050 the data shown with black solid lines correspond to merged data maps, whose fluxes are similar to those from the OTF observations. The zero level is dotted.