Distribution of the 70 697 clusters composed of four images and 2 058 962 clusters composed of three images extracted from the Gaia DR2 (see Sect. 2) with respect to their ERT probabilities (solid line). The distribution of the known lenses are represented as boxes, whereas the distribution of the 6,944 clusters resulting from the cross-match we performed between our entire list of clusters and our compiled list of quasars is depicted as a dotted line in each graph (see Sect. 3.4.2). In cases where clusters are composed of three images, the ERT probability corresponds to the maximum of the ERT probabilities returned by the ABC, ABD, ACD, and BCD models.