  It has been asserted in the literature that the analogy between the linear
and first order slow motion approximation of Einstein equations of General
Relativity (gravitomagnetic equations) and the Maxwell-Lorentz equations of
electrodynamics breaks down if the gravitational potentials are time dependent.
  In this work, we show that this assertion is not correct and it has arisen
from an incorrect limit of the usual harmonic gauge condition, which
drastically changes the physical content of the gravitomagnetic equations.
