https://www.nature.com/articles/nature.2013.14328#/b1
https://www.nature.com/articles/478302a
http://www.nucleares.unam.mx/~alberto/apuntes/zaanen.pdf
https://www.sciencedaily.com/releases/2015/04/150427101633.ht
https://arxiv.org/pdf/1501.00007.y buy
https://academic.oup.com/ptep/article/2021/12/123B05/6413569