This is the model for any online resources you might use. Make sure you include the four pieces of information: author, date, title (with a description of the format in brackets), and the source (the URL).
Provide the specific date for content that is published frequently such as blog posts.
Include the name of the website if it is not clear from the URL. For example: Retrieved from Site Name website: http://xxxxx
Provide a retrieval date for content that might change.
Use a permalink for web resources when possible.
When citing an entire website or webpage, but not a specific document or text, it is sufficient to refer to the name of the website and provide the URL in the text of your paper. No reference list entry is required. For example:
President Obama often used Twitter (http://www.twitter.co/barackobama) and Facebook (http://www.facebook.com/barackobama) to keep citizens up to speed on his initiatives.