On subgroups of GLn (Fp).
On subgroups of the general linear group over the skew field of quaternions which contain the symplectic group.
On subnormal subgroups of linear groups.
On suborbital graphs for the normalizer of .
On supersoluble groups acting on Klein surfaces.
On symplectic groups over polynomial rings.
On the Albanese variety of the moduli space of polarized K3 surfaces.
On the automorphism group of a toroidal hypermap
On the congruence subgroup problem, II.
On the Congruence Subgroups Problem: Determination of the "Metaplectic Kernel".
On the congruence-subgroup problem for some anisotropic algebraic groups over number fields.
On the connectedness of the locus of real Riemann surfaces.
On the construction of non-congruence subgroups
On the Cuspidal Cohomology of the Bianchi Modular Groups.
On the Homology and Cohomology of Congruence Subgroups.
On the Margulis constant for Kleinian groups. I.
On the number of facets of three-dimensional Dirichlet stereohedra. II: Non-cubic groups.
On the number of subgroups of given index in the modular group.
On the principal congruence subgroups of the Hecke-group .
On the representations of GL (2). II. ...-factors of the representations of GL(2) x GL(2).