https://w3id.org/np/l/nanopub-query-1.1/api/ RASCMrcymSnMAoNI28MHCwHMXhEP3Z8VoLbsdUdls98Uk/get-calls-for-proposals?searchterm=
date when the materialisation was first published (e.g. 2020-12-31)
full URI (e.g. handle.net) or short suffix
MIME type, such as "text/csv" or "application/trig"