Is it acceptable to cite an article from a corporate website? Can Wikipedia be used to prove credibility?
I agree with the answers posted here so far, but I want to add a few points.

You can realistically use any source in your paper, but it depends on how you use it. If you want to write about what X company says about a particular topic, then using that particular web article seems appropriate. If you want to write something informative about a particular product that X company happens to use, then citing that article (written by X company) is a less than ideal choice. As @Buffy mentioned, the company has a vested interest in portraying the product in a certain way, but as @Richard Erickson mentioned, this article (or Wikipedia) can be a good initial stepping stone.

Articles that you use for information need to be peer reviewed in order to have a high level of credibility. Not having access to books is not a valid excuse; universities have a plethora of resources for this exact circumstance. I recommend Inter Library Loan (ILL) for hard to get books and journal articles. Your professor may have suggestions on where to start.

tl;dr:


you can use anything as a source (even Wikipedia), but it depends on how it’s used
peer reviewed sources are best for research credibility
you can find obscure resources using your university’s library privileges
consult with your professor