Butin, F. 2015. “Branching Law for the Finite Subgroups of $SL_4ℂ$ and the Related Generalized Poincaré Polynomials”. Ukrains’kyi Matematychnyi Zhurnal 67 (10): 1321-32. https://umj.imath.kiev.ua/index.php/umj/article/view/2069.