“…In the stationary setting, existence and regularity of MFGs without congestion were considered in [10], [12], [14], [22], [23] (strong solutions) and [5], [19] (weak solutions). Many other stationary problems are examined in the literature, including obstacle problems [9], weaklycoupled systems [8], multi-populations [4], and logistic problems [13]. MFGs on networks, see [1], [3], [2], are important cases of one-dimensional MFGs.…”