INSPIRE-HEP, an open access digital library for the field of high energy physics developed by Stanford University, has been the main literature database for universities, colleges, and research institutions since when?
INSPIRE-HEP:  It is the successor of the Stanford Physics Information Retrieval System (SPIRES) database, the main literature database for high energy physics since the 1970s. Stanford Physics Information Retrieval System:  It is used by universities, colleges and research institutions.
i don't know