There are several reasons for the un linked titles. It could be that the publication is in a country's local publisher a non-English one, or that it is only a citation, or the link is broken for some reason, or it is a report or a white paper that do not have a publisher's site or a journal location.
Scholar reports "[CITATION]" to let you know it has only been able to discover a reference to the document. Scholar has detected the existence of the document from another paper's reference list. It may also be that the document is only available on paper and has not been scanned. Make friends again with your departmental librarian, and ask for it to be ordered through InterLibrary Loan.