  Given a manifold M, it is natural to ask in how many ways it fibers
  (we mean fibering in a general way, where the base might be an orbifold --
this could be described as Seifert fibering)There are group-theoretic
obstructions to the existence of even one fibering, and in some cases (such as
Kahler manifolds or three-dimensional manifolds) the question reduces to a
group-theoretic question. In this note we summarize the author's state of
knowledge of the subject.
