THE PROCESS E(-)-]L(L)OVER-BAR Q(Q)OVER-BAR AT LEP AND NLC()E()

The cross sections for the reaction e(+)e(-) --> l ($) over bar l q ($ ) over bar q and for similar four fermion production processes at LEP 1, LEP 2 and the NLC are calculated, Due to the extraordinary symmetry properties of the process, very compact analytical formulae describe the double differential distributions in the invariant masses of the I t and qa pairs. The total cross sections may be obtained with two nume rical integrations.