A finite presentation for the twist subgroup of the mapping class group of a nonorientable surface

Abstract

Let $N_{g,s}$ denote the nonorientable surface of genus g with s boundary components. Recently Paris and Szepietowski obtained an explicit finite presentation for the mapping class group $M(N_{g,s})$ of the surface $N_{g,s}$, where $s\in{0,1}$ and $g+s>3$. Following this work we obtain a finite presentation for the subgroup $T(N_{g,s})$ of $M(N_{g,s})$ generated by Dehn twists.