Isogenies between $K3$ surfaces of the Apéry-Fermi pencil

Marie José Bertin, Odile Lecacheux

Elliptic fibrations of $K3$ surfaces belonging to the Apéry-Fermi pencil ($Y_k$) may have $2$ or $3$-torsion sections defining on $(Y_k)$ automorphisms $\ddot{I}„$ of order $2$ or $3$. F…