Let L=diag(1,1,β¦,1,β1) and M=diag(1,1,β¦,1,β2) be the lattices
of signature (n,1). We consider the groups Ξ=SU(L,OKβ) and
Ξβ²=SU(M,OKβ) for an imaginary quadratic field
K=Q(βdβ) of discriminant D and it's ring of integers
OKβ, d odd and square free. We compute the Hirzebruch-Mumford
volume of the factor spaces Bn/Ξ and Bn/Ξβ².
The result for the factor space Bn/Ξ is due to Zeltinger, but
as we're using it to prove the result for Bn/Ξβ² and it is hard
to find his article, we prove the first result here as well