Nonnegative solutions for a system of impulsive BVPs with nonlinear   nonlocal BCs
  We study the existence of nonnegative solutions for a system of impulsive differential equations subject to nonlinear, nonlocal boundary conditions. The system presents a coupling in the differential equation and in the boundary conditions. The main tool that we use is the theory of fixed point index for compact maps. 
Gennaro Infante and Paolamaria Pietramala
math.CA