Usage Statistics: Consider Crossref Citation API, OpenAIRE Usage Counts and DataCite Sashimi as additional sources for OPERAS Metrics

[tosteiner]

In the context of our development of Thoth Sphinx as a usage statistics service, it might be good to consider integration of

• OpenAIRE Usage Counts: https://usagecounts.openaire.eu/
• DataCite Sashimi: https://github.com/datacite/sashimi

as sources to feed into OPERAS Metrics. Zenodo is sending usage stats to these services, so instead of plugging Zenodo directly into OPERAS Metrics, it might make sense to consider those other meta-sources.

Additionally, Crossref has announced they are sunsetting their Events data API by April 23, 2026, moving to a new Citations API endpoint.