COMPLETE INITIAL-STATE QED CORRECTIONS TO OFF-SHELL GAUGE BOSON PAIR PRODUCTION IN E(-)-ANNIHILATION()E()

We study Standard Model four-fermion production in e(+)e(-) annihilati on at LEP2 energies and above using a semi-analytical approach. We der ive the complete QED initial state corrections (ISR) to the reactions e(+)e(-) --> (Z(0)Z(0)) --> f(1)<(f)over bar (1)>f(2)<(f)over bar (2)> and e(+)e(-) --> (W+W-) --> <(f)over bar (u)(1)>f(1)(e)f(2)(u)<(f)ove r bar (d)(2)> with f(1) not equal f(2) and f(i) not equal e(+/-), ((-) )nu(e). As compared to the well-known universal s-channel ISR, additio nal complexity arises due to non-universal, process-dependent ISR cont ributions from t- and u-channel fermion exchanges. The formulae needed to perform numerical calculations are given together with samples of numerical results.