The APA reference list structure should be as follows:
This guide contains examples of items in a reference list. Some are straightforward such as books, journal articles, ebooks and dissertations. Other material that you may use in an assignment might be more difficult to define. To help solve this issue, you can utilise a simple template.
The template to use, for materials like this, contains only four pieces of information (author, date, title, and source):
Author, A. (date). Title of document [Format description]. Retrieved from http://xxxxxxxxx
The format description in brackets is used only when the format is something out of the ordinary, such as a blog post or lecture notes; otherwise, it's not necessary. Some other example format descriptions are listed on p.186 of the APAPublication Manual.
While the Publication Manual provides many examples of how to cite common types of sources, it does not provide rules on how to cite all types of sources. In this situation, APA suggests that you find the example that is most similar to your source and use that format. For more information, see p.193 of the Publication Manual of the American Psychological Association, (6th ed., 2nd printing).