Crossref similarity score changes

[essepuntato]

Few times ago, Crossref has drastically changed the value of its similarity score returned by their API. In OpenCitations, the previous threshold for having a reference considered was 2.7, while now is 75.0.

Thus, it is possible that some of the citations are not totally corrected. For instance, https://w3id.org/oc/corpus/br/2384516 cites https://w3id.org/oc/corpus/br/2384552, while it should cite "Ciccarese, P., Shotton, D., Peroni, S., Clark, T. (2014). CiTO + SWAN: The Web Semantics of Bibliographic Records, Citations, Evidence and Discourse Relationships. In Semantic Web – Interoperability, Usability, Applicability, 5 (4): 295-311.".

The bug has been corrected in the current version, but an appropriate recheck of the whole corpus should be done so as to understand how this change has affected the citation links.