This article was widely discussed leading up to the 2016 election which is how I came to find it and read it. It probably had a link in a post within a thread.
This article did not cite a court decision because there is none, but I believe that it does represent the opinion of the vast majority of the judiciary. The article does not address the other issue with the term Natural Born Citizen, to wit: Anchor babies. Children born within the borders of the United States are U.S. Citizens at birth (except children of the diplomatic corps) and are not required to undertake naturalization proceedings.
Not having to go through naturalization does not prove anything. When Aliens become citizens, their small children do not have to go through a naturalization process. When their parents naturalize, the children acquire "derivative" naturalization. They are naturalized without having to go through a naturalization process.