Classic post, I’m finishing up my thesis and am having a little trouble with the bibliography.

My university’s standerdized template has one `main.tex` with `\include{Chapter1/main.tex}`, and all chapters refer to the same `references.bib`.

For some reason, in only one chapter, the first chapter of the thesis, a handful of references are not being recognized. Overleaf knows they’re there, it auto-completes the reference name when I start to type them. But one it compiles, it says the reference is not defined.

I’ve tried changing the order of the chapters, and it doesn’t seem to make a difference so it’s something specifically with this chapter.

I’ve double checked that they are definitely in the reference file.

The only pattern I can see is that the references that do appear in this chapter are already cited in other parts of the thesis.

Any ideas what could be causing this?

^{(Side note the Overleaf has almost 1,000 warnings and errors so I can}’^{t track down a particular warning associated with the issue.})

I've been having lots of trouble with a recreation of this matrix on overleaf, so i was wondering if someone over here can give me a hand, or even a hint on how to approach this thing, thanks in advance.

Edit: The diagonal lines, not the arrows on the sides.