Introduction
I am a blind undergraduate studen in mathematics. I use screen reading software, which uses synthesized speech to read aloud the contents of the screen, to read and write math.
Due to the limitations in presentation-focused formats like PDF and MathJax, screen readers can't properly handle most mathematical content contained in them.
This means that for the most part, I can only properly access math documents in their source format, like LaTeX; this severely limits the resources have access to for studying. Thankfully, there are some excellent online math resources that include content sources, like Wikipedia and NLab, but sometimes these aren't enough on their own to learn a topic well.
Sometimes I've had luck reaching out to kind lecturers and publishers about particular textbooks, which they were able to provide in source format; but in general it's very hard to find other good learning resources available in source form.
One other good resource is Arxiv, which often allows you to download the source of an article, but it's very hard to search through the mountains of articles specifically for educational resources.
The Request
What would be really nice is a comprehensive listing by topic of educational math resources that people have made available online in source form; and this is what I would like this question to become.
So: if you have (or know of) lecture notes, textbooks, or the like, that are available online in source form, via Arxiv, or somewhere else, then post it as an answer, and I will keep the question updated with a categorized list. (Note: There is no special processing needed to make LaTeX screen-reader-friendly.)
Thank you in advance for making the lives of blind mathematics students easier.
P.S. I hope that this is an appropriate place to make this post; sorry in advance if it isn't.