I have been scanning the net for studies which are for and against various aspects of the Doctrine of the Trinity. I have to say that the nay-sayers are not unsophisticated in their arguments. If the Trinity teaching is so widely subscribed to, how does one explain so many negative references which appear in such standard academic works as The Encyclopedia Britannica, The Encyclopedia Americana, The New Catholic Encyclopedia, etc.?
I'm afraid that you will indeed find that many academic reference works oppose the doctrine of the Trinity. This is often true because many of these reference works are written by people who are more interested in discrediting this doctrine than in supporting it (such as liberal Christians and non-Christians). At other times, you may be reading portions of works supporting the doctrine of the Trinity, but quoted by those oppose it. One can almost always quote a qualification in a way that makes it sound like it is a refutation instead of qualification.
In any case, I think I can offer a few general explanations that will apply to many of the works you encounter:
Ra McLaughlin is Vice President of Finance and Administration at Third Millennium Ministries.