@article{AIHPD_2022__9_3_473_0,
     author = {Hu, Simone and Schnetz, Oliver and Shaw, Jim and Yeats, Karen},
     title = {Further investigations into the graph theory of $\phi^4$-periods and the $c_2$ invariant},
     journal = {Annales de l{\textquoteright}Institut Henri Poincar\'e D},
     pages = {473--524},
     volume = {9},
     number = {3},
     year = {2022},
     doi = {10.4171/aihpd/123},
     mrnumber = {4525139},
     zbl = {1520.81075},
     language = {en},
     url = {http://archive.numdam.org/articles/10.4171/aihpd/123/}
}