I've found mention of them BUT, I don't find them. Ideally, I seek the all-positive versions. Thanks!
André is right. I found a Portuguese one for you: http://meiert.com/en/blog/20091127/sus-how-to-grade/ (near the bottom of post, in updates).
There's also a good chance that you are seeing references to versions of the SUS that the researchers themselves have translated.