The author of LotR clearly intended it to be a single book, and it was sold as one concurrently with the three-volume editions as soon as it became popular enough to be economically feasible.  The utilitarian separation of the book into three volumes does not seem to me to be sufficient reason to declare it to be three separate books.  This is in stark contrast with Rowling's books, which have been published sequentially, separated by years in between them, and are considered by everyone (including the author and publisher) to be separate books entirely.  I agree that the individual books deserve a place on this list inasmuch as they merit one, and that the series as a whole belongs on the series page.  I hope we can put this matter to rest now.  Thank you for your time.