Parkkonen, Jouni, and Frédéric Paulin. “A Classification of $\mathbb{C}$-Fuchsian Subgroups of Picard Modular Groups”.
MATHEMATICA SCANDINAVICA
121, no. 1 (September 22, 2017): 57–74. Accessed April 3, 2025. https://www.mscand.dk/article/view/26128.