Add all links to bibtex

The bibtex file was configured so that the links didn't show up. This prq fixes that.

Before:
![image](https://cloud.githubusercontent.com/assets/1488921/5166777/1d0c689e-73f3-11e4-8e36-2c2382aee6ee.png)

After:
![image](https://cloud.githubusercontent.com/assets/1488921/5166759/0577974e-73f3-11e4-8a24-04ed69b232eb.png)