Is there a database of publications for nearly all major disciplines? Google scholar is an excellent service for looking at basic metadata about publications (e.g. authors, title, abstract, and papers it cites). But they do not offer an official API (free or otherwise).
Is there also a non-commercial database of such publications? I'm wondering because this is something that perhaps libraries in universities would require to organize information about publications across disciplines.
Since there are non-profit systems like doi.org and cross-ref which let publications get an identification numbers, I'm wondering if all disciplines use them. Or is it the case that universities get this metadata from a variety of publishers (like Springer, Elsevier, etc) and there is no single central index?
To avoid bikeshedding on what a &quot;major discipline&quot; is, we could limit ourselves to what's already found on google scholar, or perhaps to what top 100 (or choose your number) university libraries in the world might index.
LENS.org offers a free API comprising data from ca. 224 million scholarly work (according to that page about the API).
In comparison, CrossRef has ca. 120 million records (source), also with an API.
But note that the metadata from both LENS and CrossRef are limited. For instance, they do not track self-cites, they do not analyse author collaboration networks, they do not generate author profiles through algorithms (though LENS seems to plan doing so with the help of ORCiD). For such advanced purposes, commercial databases such as Web of Science, Scopus, or Dimensions are the go-to platforms.