André Du Nay appears as the author of one book, The Origins of the Rumanians: The Early History of the Rumanian Language, Toronto; Buffalo: Matthias Corvinus Pub. reviewed here on a respectable website.
I have not yet read the book, but it contains this note:
An earlier version of this book appeared in 1977 as Edward Sapir Monograph No. 3, published by Jupiter Press, Lake Bluff, IL, (ISBN 0–933104–03–0, Library of Congress No. 79–115770).
It also contains thanks to, and a preface by Adam Makkai, Professor of Linguistics, University of Illinois at Chicago, a native Hungarian.
”André Du Nay” sounded a bit odd to me, I thought maybe it is a pseudonym. But I wasn't able to find anything more, not even about the academic status and carrier of this author.
Is there a chance to find more about him?