How to add link to referecne?

Question

I am writing a thesis and I would like to add link to references. Below sample code from file "references.bib":

@article{simpleLink,
author = {},
journal = {},
number = {},
pages = {},
title = {},
url = {www.wikipedia.com},
volume = {},
year = {}
}

The problem is that this link is not visible when I compile the file. In document I see author, title, journal, etc. ,but I can't see url (link -> www.wikipedia.com). How can I solve it? Thanks.

This is the template, which I am using:

https://drive.google.com/file/d/0BwyOySLlDTB_a3R5aFZQNzVFRG8/edit?usp=sharing