title: On subgroups of crystallographic Coxeter groups.
abstract: A framework is presented based on color symmetry theory that will facilitate the determination of the subgroup structure of a crystallographic Coxeter group. It is shown that the method may be extended to characterize torsion-free subgroups. The approach is to treat these groups as groups of symmetries of tessellations in space by fundamental polyhedra.
authors.affiliation: Mathematics Department, Ateneo de Manila University, Loyola Heights, Quezon City, 1108, Philippines.
authors.forename: Eden Delight B
authors.initials: ED
authors.lastname: Provido
authors.forename: Ma Louise Antonette N
authors.initials: ML
authors.lastname: De Las Peñas
authors.forename: Rene P
authors.initials: RP
authors.lastname: Felix
keywords: color symmetry; crystallographic Coxeter groups; crystallographic groups; subgroups of crystallographic groups; torsion-free subgroups