Here is a sample record from PubMed Central.

Two methods for linking.
1. To the reference - replace the PMCID number in the following URL with the PMCID number for your article reference.
http://www.ncbi.nlm.nih.gov/pmc/?term=PMC2686545
2. To the PDF of the article - Once you have the reference displayed in PubMed, right click on the PDF link and select "Copy Link Location"

Finally, paste the link where you want to use it. Since these articles are freely available, do not include the EZproxy prefix.