“…For the case of closed manifolds, the last decade of research led to tremendous progress on this question, see, for instance, [2,3,19,22,23,25,27,28,29,30,37,38]. On the other hand, face numbers of manifolds with boundary remained a big mystery, and very few papers even touched on this subject, see [9,14,25,28]. At present there is not even a conjecture for characterizing the set of f -vectors of balls of dimension six and above, see [14].…”