Column densities of (complex) organic molecules toward CALYPSO sources. The color coding of the molecules is indicated at the bottom. Secure detections are shown as plain bars, tentative detections as hatched bars, and upper limits as empty bars with a downward arrow. The name of each source is indicated in each panel. Two rightmost panels in the bottom row: column densities of two other Class 0 protostars collected from the literature (see Sect. 3.7 for references).