/Biz/ness man here that needs your help /sci/, does anyone have any good sources to learn more of the math behind finance, more in the quant realm of things? My more basic understanding of math is actually starting to become a big problem in my research, as the concepts I grasp become more specialized I am having trouble digesting the content because I cannot understand the math well behind it. Specifically I was trying to digest this article today and was getting completely lost:

Rogerlord [DOT] cm [SLASH] ufrtopquants [DOT] pdf

It's not like im completely deficient, I can do many necessary functions in finance, but I don't even know what resources are available for tackling something like this. Thank you for any help you can provide, and sorry for the shitty link format it kept being marked as spam.