I forget his name, but he was an attorney and he wrote a lot on the topic. It wasn't Mario Apuzo, who did excellent work on the subject. I forget the other guy's name, but he is the one that broke the story that Chester A Arthur's father was not a citizen before Arthur was born.
Anyone remember that guy's name? He also used to have a website. I also remember he fancies himself as a professional gambler at cards.
Here is the book you are probably thinking about: https://www.iuniverse.com/en/bookstore/bookdetails/775911-Imposters-in-the-Oval-Office
To All:
List of U.S. Presidents – Eligibility under Article II Grandfather Clause (GFC) or Natural Born Citizen (NBC) Clause or Seated due to Election Fraud: https://cdrkerchner.wordpress.com/2011/09/23/list-of-u-s-presidents-eligibility-under-article-ii-grandfather-clause-gfc-or-natural-born-citizen-nbc-clause-or-seated-due-to-election-fraud-3/