A Geometric Presentation of the λ2-Modules of C(n)(q) and D(n)(q) Original Research Article

The fixed-point sheaf of the λ2-module V for each of the groups Cn(q) and Dn(q) is constructed. It is shown that the 0-homology module of the sheaf is isomorphic to V. This gives a presentation of V by geometric generators and relations.