Let T be a binary tree. In RCA0, I wanted to show that (T,<) is a linear ordered structure where < means the lexicographic ordering on T. I tried to prove it, and I did. I think my proof works; but it became too long. It is a little part of my dissertation project, and I don't want to write about it too much. So I decided to use a reference.
could you please introduce me some textbook, paper, etc which in that, it somehow claims that (T,<) is a linear ordered structure? This will do, but Better If it has proved it.
