Interference of outgoing electromagnetic waves generated by two   point-like sources
  An energy-momentum carried by electromagnetic field produced by two point-like charged particles is calculated. Integration region considered in the evaluation of the bound and emitted quantities produced by all points of world lines up to the end points at which particles' trajectories puncture an observation hyperplane $y^0=t$. Radiative part of the energy-momentum contains, apart from usual integrals of Larmor terms, also the sum of work done by Lorentz forces of point-like charges acting on one another. Therefore, the combination of wave motions (retarded Li\'enard-Wiechert solutions) leads to the interaction between the sources. 
Yurij Yaremko