On electromagnetic energy in Bardeen and ABG spacetimes
  We demonstrate that the total energy of electromagnetic field in the Bardeen and Ay\'on-Beato-Garc\'ia singularity-free models is equal to the mass parameter $M$, being therefore independent of the charge parameter $Q$. Our result is fully congruent with the original idea of Born and Infeld to use nonlinear electrodynamics for proving the electromagnetic nature of mass. 
V.S. Manko, E. Ruiz
gr-qc