# Fundamental pair of periods

Let $f \colon X \rightarrow \mathbb{C}$ be a doubly periodic function with periods $\omega_1$ and $\omega_2$. We say that the ordered pair $(\omega_1,\omega_2)$ is a fundamental pair of periods if every period of $f$ is of the form $m\omega_1+n\omega_2$ for all integers $m,n$.