lv-diagram of the supershell GS242-03+37 with the outlines. Left panel: outlines of the best model (“basic model” at 120 Myr, blue/white), the model with twice the energy input at 100 Myr (violet/black), and the approximate outline of the observed structure (grey line). Right panel: outlines of the best (basic) model (blue/white) and of models with the fixed ages (40 Myr: green/black; 80 Myr: violet/black). HI map is underlined; black contours show the CO emission. The colour scale is .