[en] The most general covariant spinor derivative compatible with the Minkowski line elements leads in a unique way to an antisymmetric torsion tensor. It turns out that this can be expressed by means of a pseudovector potential, counterpart of the usual vector potential of electrodynamics. In this way some of the models for a symmetrized theory of the electromagnetic interaction with spin-1/2 particles are rederived. (author)