The industry standard for citations between scholarly publications is CrossRef, which is the official DOI link registration agency for scholarly and professiona

The industry standard for citations between scholarly publications is CrossRef, which is the official DOI link registration agency for scholarly and professional publications. I don't know what the original document said, but if it was a scholarly publication, the citation should/could have been done by DOI. DOIs resolve to URLs, but publishers have a mandate to keep them up-to-date. http://crossref.org http://crossref.org http://en.wikipedia.org/wiki/Digital_object_identifier http://en.wikipedia.org/wiki/Digital_object_identifier http://www.doi.org/ http://www.doi.org/ (I work for CrossRef)