From the article: "Today the Google Analytics team announced that we will start seeing backlink URLs in their newly released Social Reports. According to the announcement post, written by Ilya Grigorik, Software Engineering Manager, Google Analytics (and PostRank Founder):
“These reports provide another layer of social insight showing which of your content attracts links, and enables you to keep track of conversations across other sites that link to your content.
Most website and blog owners had no easy mechanism to do this in the past, but we see it as another important feature for holistic social media reports.
When you know what your most linked content is, it is then also much easier to replicate the success and ensure that you are building relationships with those users who actively link to you the most.”
Where To Find The Backlink URLs Report
The Backlink information is not easy to find."
Here all of the information to find out more: http://searchengineland.com/google-analytics-backlink-report-120235