Integral manifolds of differential equations with piecewise constant   argument of generalized type
  In this paper we introduce a general type of differential equations with piecewise constant argument (EPCAG), and consider the problem of backward continuation of solutions. We establish the existence of global integral manifolds of quasilinear EPCAG, consisting of infinitely back continued solutions, while the solutions starting outside the invariant sets may not be back continued. The smoothness of the manifolds is investigated. The existence of bounded and periodic solutions is considered. A new technique of investigation of equations with piecewise argument, based on an integral representation formula, is proposed. 
Marat Akhmet