When in doubt, ask your instructor which citation style to use for your paper or project. Some of the most widely used citation styles include:
Since 2000 there has been an effort to assign everything that exists in the digital world, e.g. online articles, with a unique number called a Digital Object Identifier or a DOI. The DOI is unique, permanent, and persistent. It remains the same despite changes in URL's or permanent removal from the Internet.
In APA and AMA citation styles, use the DOI in citations whenever one is listed.
When you cite a full-text article retrieved from a Webster University Library database, some citation styles require you to cite the database name and/or a URL. Here’s how the University's most-used citation styles address this issue: