Examples of OCs (blue dots) harboring classical Cepheids (red hexagram). The columns of each panel represent the distributions of the member stars of OCs and classical Cepheids for position in RA (α) and Dec (δ), proper motions in µ_α* and µ_δ, and the CMD in G vs. G_BP – G_RP, as well as the mean parallax and total proper-motion dispersion of OCs. Here, the listed OCs are Berkeley 58, NGC 103, and NGC 129.