I am a mathematician studying DNA and RNA language from the perspective of Formal Language Theory. Note that I am aware of these posts:
I consider my situation more specific, I am specifically dealing with DNA and RNA, so what I need is a basic text that deals with this two structures, rigorous but still accessible.
As an example I quote a paper I am reading:
(...) Inverted repeats are prevalent features of nucleic acids (...)
I would like trustable references for the fact that these features indeed exist, which is fundamental for my work, and maybe a shallow explanation for what they biologically imply, but I do not want to delve into what these features mean (It would be great to understand them from a biological perspective but that is not my priority)