Unresolvable Identifier

arXiv:2604.21745 · detector doi_compliance · cross_source · 2026-05-20 00:42:40.111017+00:00

critical doi_compliance unresolvable_identifier

Identifier '10.1515/crll.1909.136' is syntactically valid but the DOI registry (doi.org) returned 404, and Crossref / OpenAlex / internal corpus also have no record. The cited work could not be located through any authoritative source.

Paper page Integrity report arXiv Try DOI

Evidence text

E. Hellinger. Neue begründung der theorie quadratischer formen von unendlichvielen veränderlichen. Journal für die reine und angewandte Mathematik, 136:210–271, 1909.DOI: 10.1515/crll.1909.136

Evidence payload

{
  "arxiv_id": null,
  "checked_sources": [
    "crossref_by_doi",
    "openalex_by_doi",
    "doi_org_head"
  ],
  "doi": "10.1515/crll.1909.136",
  "raw_excerpt": "E. Hellinger. Neue begr\u00fcndung der theorie quadratischer formen von unendlichvielen ver\u00e4nderlichen. Journal f\u00fcr die reine und angewandte Mathematik, 136:210\u2013271, 1909.DOI: 10.1515/crll.1909.136",
  "ref_index": 28,
  "verdict_class": "cross_source"
}