The A.P.A. style is a relatively sleek method of citing that emphasizes author and date information. It is oriented toward the use of journal articles, though there are rules included in the manual that pertain to references to books, newspapers, and popular magazines. Look at the A.P.A. website (link provided below) for guidance on citing Facebook, Twitter, and other social media.
Here are a few helpful citation pages:
A doi (digital object identifier) provides a persistent internet link to an article. APA style recommends including the doi in references whenever they are available.
How can I find the doi in an article?
1. Look in the database record for the doi field.
2. Look in the article itself (usually the first page of the article, near the title or abstract).
3. Use the CrossRef free service that retrieves the doi from bibliographic information. Type in the elements of a citation to search for an article's doi.
Keep in mind that the doi is not always available, even in articles published in peer reviewed journals, though its use is increasing.
See below for the doi field in PsycArticles EBSCOhost. It's near the bottom of the record.
Below is an example of the doi found on the first page of an article.