Welcome to the Q&A Forum

Are you asking about a page that has a canonical link which is the same as the URL of the page? That is quite common, and not a problem. (Take a look at the source code of this page--you will see Moz has used a canonical that is the same as the URL.)

From the example URLs you posted it does count as duplicate content. If you still need to keep all 3 URLs I would look into canonicalization. See here: http://moz.com/learn/seo/canonicalization and here http://googlewebmastercentral.blogspot.ca/2013/04/5-common-mistakes-with-relcanonical.html Also I would recommend taking a look at this article http://moz.com/learn/seo/duplicate-content Hope it helps