“…On the other hand, in [10] it has turned out to be beneficial to work on the system (1.1), (1.3) instead, since it allowed to derive powerful a-priori estimates on u ε . The analysis in the older studies [9] and [10] relied on the existence of an upper bound ζ max of the function ζ. In [10], for fixed ε, we prove existence and uniqueness of weak solutions of the coupled system (1.1), (1.2), (1.3).…”