On Optimal Recovery of Integrals of Set-Valued Functions
  In this paper we consider the problem of optimization of approximate integration of set-valued functions from the class defined by given majorant of their moduli of continuity, using values of the functions at $n$ fixed or free points of their domain. We consider the cases of exact information and information with error. 
V. F. Babenko, V. V. Babenko, M. V. Polischuk
math.FA