  We prove the equivalence of (a slightly modified version of) the
wall-crossing formula of Manschot, Pioline and Sen and the wall-crossing
formula of Kontsevich and Soibelman. The former involves abelian analogues of
the motivic Donaldson-Thomas type invariants of quivers with stability
introduced by Kontsevich and Soibelman, for which we derive positivity and
geometricity properties.
