Modular curves and Poncelet polygons.
Modular curves and the Eisenstein ideal
Modular embeddings and rigidity for Fuchsian groups
We prove a rigidity theorem for semiarithmetic Fuchsian groups: If Γ₁, Γ₂ are two semiarithmetic lattices in PSL(2,ℝ ) virtually admitting modular embeddings, and f: Γ₁ → Γ₂ is a group isomorphism that respects the notion of congruence subgroups, then f is induced by an inner automorphism of PGL(2,ℝ ).
Modular embeddings for some non-arithmetic Fuchsian groups
Modulflächen quadratischer Dikriminante.
Motives for Hilbert modular forms.
Motives for modular forms.