Lets examine the definition of article-# A nonfictional literary composition that forms an independent part of a publication, as of a newspaper or magazine.
Well see, there's yer problem!
As you probably don't know, composition means: the act of combining parts or elements to form a whole. In this case letters and articles from the parts of the whole (Journal of 9/11 Studies). A short essay, especially one written as an academic exercise.
Um yea... The thing is based on the context I think there's a very reasonable and strongly implied assumption that by "peer reviewed" means published in a reviewed journal like The Journal Science or Nature or the New England Journal of Medicine or the British Medical Journal or the Canadian Journal of Radiology or the Journal of the American Acadamy of Sciences or something.
I guess it's something of a subjective and "fuzzy" definition of what would be legitimate peer review but I think most people would not consider a bunch of other 9/11 CT'ers reviewing it to count. Even if they are his "peers."
And as far as "paper" I think most would tend to think that means a formal and full writeup is published in such a journal and not in the editorial section either. Something that an accademic institution might reasonably cite and such.
I mean if you want to go with the strict technical definition of paper then I could claim all the square "paper" I went through wiping my backside after having a bit too much mexican food as papers on the topic of international relations in the western hemisphere.