We specify an algorithm that builds up a hierarchy of referential discourse
segments from local centering data. The spatial extension and nesting of these
discourse segments constrain the reachability of potential antecedents of an
anaphoric expression beyond the local level of adjacent center pairs. Thus, the
centering model is scaled up to the level of the global referential structure
of discourse. An empirical evaluation of the algorithm is supplied.Comment: LaTeX, 8 page