Upper-left panel: (HC(O)NH₂) as a functionof (HNCO). Upper-central panel: (CH₃NCO) as a functionof (HNCO). Upper-right panel: (CH₃NCO) as a functionof (HC(O)NH₂). Bottom-left panel: (CH₃C(O)NH₂) as a functionof (HNCO). Bottom-central panel: (CH₃C(O)NH₂) as a functionof (HC(O)NH₂). In all the panels, the solid lines are the power-law fit obtained in this work, and the different colours represent the different sources, as indicated in the bottom-right legend. Data are taken from the same works indicated in Fig. 16.