A core ecosystem service is refining and cleaning data. This can include callouts to other services (dab, recon, spellcheck). In general, a cleaning service describes the category of messiness it addresses, takes in data and returns a hopefully-cleaner version of it.
A core underlay service is disambiguation: explicitly linking entities to identifiers from different source namespaces. Each identifier can resolve different sorts of ambiguities, and a combination of identifiers may still have ambiguity or conflicts.
Authors of papers: Crossref
Proposals: In biomedicine (Piwowar 2018)
Article titles: Crossref
Hinted at by shape constraints on potentially-conflicting or convolved data being reconciled; made explicit by defining reconciliation steps [reductions, tests] to ensure constraints are satisfied.
The end goal of cleaning, dab, recon, and reduction.
Specific notions of this: dbpedia fusion.