reserve S,T,W,Y for RealNormSpace;
reserve f,f1,f2 for PartFunc of S,T;
reserve Z for Subset of S;
reserve i,n for Nat;

theorem
  for p be Element of S, r be Real st 0 < r holds
    Ball(p,r) <> {} & cl_Ball(p,r) <> {} by LMBALL2;
