We analyze the production in e+e− collisions of new heavy fermions
stemming from extensions of the Standard Model. We write down the most general
expression for the production of two heavy fermions and their subsequent
decays, allowing for the polarization of the e+e− initial state and
taking into account the final polarization of the fermions. We then discuss the
various decay modes including cascade and three body decays, and the production
mechanisms, both pair production and single production in association with
ordinary fermions.Comment: 21 pages (no figures), Preprint UdeM-LPN-TH-93-15