Q. What does DOI mean in a citation?

The DOI (Digital Object Identifier) number is used, when available, for citing electronic resources. The DOI is a unique alphanumeric string, beginning with 10, assigned by a registration agency (the International DOI Foundation) to identify content and provide a persistent link to its location on the Internet.

Generally, journal, magazine and newspaper articles should be cited just as they would be in print formats, followed by the name of the database used or the DOI information.