%0 Journal Article
%A H. Katsuura 
%T Dihedral Angles of 4-Ball Tetrahedra
%J Journal for geometry and graphics
%D 2021
%P 197-204
%V 25
%N 2
%I mathdoc
%U http://geodesic.mathdoc.fr/item/JGG_2021_25_2_JGG_2021_25_2_a3/
%F JGG_2021_25_2_JGG_2021_25_2_a3