1929 The Lehmann-Symanzik~Zimmermann formalism is presented for manifestly covariant quantum electrodynamics involving, a gauge parameter a. Contrary to Kiilll5n's assertion, it is shown that one can consistently formulate the asymptotic condition for the electromagnetic field and construct the Fock space of asymptotic states. Except for the case of Feynman gauge (a=1), the formalism ,is somewhat complicated because of the presence of dipole ghosts, but , emphasis is laid on the very existence

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... f a consistent formalism. The completeness relation for the asymptotic states, is presented so that the generalized unitarity relation can be written down. Indefinite-metric' theory of a massive vector field is briefly discussed.