If you publish results based on this graph, please quote the references suggested in the dataset page.
This graph has been obtained from a 2005 crawl of the .uk domain performed by UbiCrawler. The crawl was very shallow, and aimed at gathering a large number of hosts, but a small number of pages from each host. Note that before April 2006 the URL order was not exactly lexicographical due to some locale issues (the graph was anyway correct). The current dataset has been correctly permuted so that URLs are ordered lexicographically.