%0 Journal Article %A Shalit, Ehud de %T Criteria for periodicity and an application to elliptic functions %J Canadian mathematical bulletin %D 2021 %P 530-540 %V 64 %N 3 %U http://geodesic.mathdoc.fr/articles/10.4153/S0008439520000624/ %R 10.4153/S0008439520000624 %F 10_4153_S0008439520000624