Theta functions on the bounded symmetric domain of type ... and the period map of a 4-parameter family of K3 surfaces. Keiji Matsumoto — 1993 Mathematische Annalen
On modular functions in 2 variables attached to a family of hyperelliptic curves of genus 3 Keiji Matsumoto — 1989 Annali della Scuola Normale Superiore di Pisa - Classe di Scienze
Configuration space of 8 points on the projective line and a 5-dimensional Picard modular group Keiji Matsumoto; Masaaki Yoshida — 1993 Compositio Mathematica
Monodromy of the hypergeometric differential equation of type (3,6) II. The unitary reflection group of order 2 9 . 3 7 . 5 . 7 Keiji Matsumoto; Takeshi Sasaki; Nobuki Takayama; Masaaki Yoshida — 1993 Annali della Scuola Normale Superiore di Pisa - Classe di Scienze
Polynomial invariants and harmonic functions related to exceptional regular polytopes. Iwasaki, Katsunori; Kenma, Atsufumi; Matsumoto, Keiji — 2002 Experimental Mathematics