The wallpaper used in this bootskin is City at Night II from the digital blasphemy members gallery. Aside from the fact that there's no permission included the watermark that Ryan puts on ALL of his walls has been removed. This is directly from the copyright page on the digitalblasphemy free site:

Under no condition will I allow any of my hi-res images to be posted without the URL watermark in the lower right corner.

I'd post a link to the source but it's on the pay site and without a login it would be fruitless.