Any discursive event of communication can invoke (index) one or more other events in the nontrivial sense that focal aspects of the ongoing entextualization presuppose that the indexing and indexed lie within some chronotope of "-eval"ness. Varied processes in distinct institutional sites in the macrosociological communicative economy shed light on the contingent varieties of such interdiscursivity. Token-sourced interdiscursivity implies a reconstruction of a specific, historically contingent communicative event as an entextualization/contextualization structure, complete in all its essentials as drawn upon. Type-sourced interdiscursivity implies normativities of form and function, such as rhetorical norms, genres, et cetera. Token-targeted and type-targeted interdiscursivities concern the characteristics of the indexing discursive event(s) as contingent happenings or normativities.