_:b57159185 <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://www.w3.org/ns/oa#TextQuoteSelector> . _:b57159184 <http://www.w3.org/ns/oa#hasSelector> _:b57159185 . _:b57159184 <http://www.w3.org/ns/oa#hasSource> <http://ns.inria.fr/covid19/arg/651e3e8f876561953588dcb671789c685b7ee16a/0> . _:b57159185 <http://www.w3.org/ns/oa#exact> "concentration" .