The flat stable module category of a coherent ring

Let R by a right coherent ring and R-Mod denote the category of left R-modules. We show that there is an abelian model structure on R-Mod whose cofibrant objects are precisely the Gorenstein flat modules. Employing a new method for constructing model structures, the key step is to show that a module is flat and cotorsion if and only if it is Gorenstein flat and Gorenstein cotorsion.