Google Scholar offers BibTeX citations for research items it retrieves, but the formatted BibTeX citation it provides does not include a digital object identifier, or DOI, for the research object described.
A better online service that allows retrieval of BibTeX-formatted citations with DOIs is doi2bib.org.
Enter a valid DOI in the form and a BibTeX-formatted display returns. The DOI can be from any DOI registration agency, be it CrossRef (mostly articles and book chapters), DataCite (datasets), or another.
This screenshot example shows the BibTeX entry returned for a DOI corresponding to a dataset in the CaltechData repository:
