Multipolar radiation and the gauge invariant reduction of multipole   tensors
  Compact general formulae for the energy, momentum and angular momentum radiated by confined systems of charges and currents are presented in terms of their multipole Cartesian tensors. Besides the usual electric and magnetic multipoles, a family of toroid (anapole) electromagnetic tensors, as well as some mean squared radii contributions are standed out through a method given in previous works of the authors. 
Constantin Vrejoiu and Cristian Stoica