@inproceedings{Boels:20167u, author = "Boels, Rutger and Kniehl, Bernd and Yang, Gang", title = "{On a four loop form factor in N=4}", doi = "10.22323/1.260.0039", booktitle = "Proceedings of Loops and Legs in Quantum Field Theory {\textemdash} PoS(LL2016)", year = 2016, volume = "260", pages = "039" }