A fixed point theorem and relative asphericity (with Colin Rourke)
L'Enseignement Mathématique 51 (2005), 231-237

We give short new geometric proofs of theorems of Bogley and Pride and of Serre. Both follow quickly from a global fixed point theorem. The Bogley-Pride theorem concerns aspherical relative group presentations and was applied in [5] to the multivariable adjunction problem. Serre's theorem is a basic result concerning group cohomology and finite subgroups.