A language model that provides answers with sources (which could be found using a traditional search engine that searches the corpus that the language model is

A language model that provides answers with sources (which could be found using a traditional search engine that searches the corpus that the language model is trained on) would be very useful and would also allow it to link directly to the source material. The trouble would be in finding the exact sources since the output of the language model is unlikely to be verbatim but current search engines can deal with imprecise queries fairly well so it's not an intractable problem. A very well curated data set would help this immensely. I'd be super interested in a language model that was able to synthesize knowledge drawn from a large corpus of books and then cite relevant sections from various titles.