A characterization of the electromagnetic stress-energy tensor
  In a previous paper, we pointed out how a dimensional analysis of the stress-energy tensor of the gravitational field allows to derive the field equation of General Relativity. In this note, we comment an analogous reasoning in presence of a 2-form, that allows to characterize the so called electromagnetic stress-energy tensor. 
J. Navarro and J.B. Sancho
gr-qc