Check out the backlinks through ahrefs and you can see that a bunch of websites with the title PHP stack just linking to them.
Here's a few examples
http://personaldividends.com/
http://www.greenpandatreehouse.com/
https://www.casino-bonus.top/
http://balancejunkie.com/
They're all expired domains too if you check out those backlinks.
Here's a few examples
http://personaldividends.com/
http://www.greenpandatreehouse.com/
https://www.casino-bonus.top/
http://balancejunkie.com/
They're all expired domains too if you check out those backlinks.