Answered By: Steve Runge
Last Updated: Sep 29, 2017     Views: 133

A doi is a digital object identifier, a widely used system of unique codes to identify digital objects, such as online articles. Many digital items (and most scholarly journal articles) are assigned unique identification codes, usually combinations of numbers, letters, and symbols. These codes allow for easy location of articles and citations of articles, both by people using search engines and by automated computer applications. Here is an example:

10.1126/science.1102896

This doi refers to this article (listed in APA style):

Novoselov, K. S., Geim, A. K., Morozov, S. V., Jiang, D., Zhang, Y., Dubonos, S. V., . . . Firsov, A. A. (2004). Electric field effect in atomically thin carbon films. Science, 306(5696), 666-669. doi:10.1126/science.1102896

Note how the doi appears at the end of the citation. Want to test it? Copy and paste the doi into a Catalog article search.