How do I reference a database using APA formatting?

I have checked the Perdue OWL guide and none of them seemed to directly apply.

What I want to reference is this website which I used to select a list of words for my experiment:

http://www.psy.uwa.edu.au/mrcdatabase/uwa_mrc.htm

I was going to use the authors names, but I cannot find them anywhere on the site. So I was wondering if there was a way to reference just the site itself?

I was thinking something along the lines of:

Machine Readable Dictionary. Website: http://www.psy.uwa.edu.au/mrcdatabase/uwa_mrc.htm

So has anyone done anything like this and can help? I’ll search for the authors names some more in the mean while.