There’s a great recent-ish survey paper at https://arxiv.org/pdf/1504.05140.pdf https://arxiv.org/pdf/1504.05140.pdf which will give you pointers to papers in a

There’s a great recent-ish survey paper at https://arxiv.org/pdf/1504.05140.pdf https://arxiv.org/pdf/1504.05140.pdf which will give you pointers to papers in all directions :)