Ebook yoga sources

Hi. I was wondering if anybody knows good sources of information for free books via epub, .pdf, etc… that are yoga-centric

here is one source that I found, though not quite what I am personally looking for, but still useful…thought I’d just share its existence with others.

…oh, guess I can’t list a url to another site yet; just add the standard opening tag to the following

swami-krishnananda.org/books_2.html