Petersen diagram for confirmed DCEP_MULTI objects published in the Gaia DR3 catalogue (red filled circles) and for additional DCEP_MULTI objects detected in the re-processing of the data (blue filled circles). P_L and P_S represent the longest and shortest pulsation periods of the multi-mode object. Labels show the typical location of the different multi-mode pulsation combinations identified in these sources. Black squares mark six objects known in the literature as ARRDs (see Sect. 6.4).