My professor is very strict about sources. All of them have to be credible, come from scholarly peer reviewed journals, and so on and so on. Shes also very strict about using fresh sources that are no more than five years old. Finding them drives me crazy. Once, I bought a paper from another site, but the writer used sources they were not supposed to use, and I had to write everything on my own from scratch eventually. Then I found this one, and its writers are much better. The representatives explained to me that the writer has to follow instructions as they are written, and now I always explain what kind of sources I need. Had no problems with the papers from this site, very satisfied so far.
Our superhero writers are happy to hear it!