Abstract Algebra
《Abstract Algebra》 · 第 636 页 · Section 14.7「Cyclic Extensions」，Exercise 9「Artin-Schreier Extensions」
9. (Artin-Schreier Extensions) Let $F$ be a field of characteristic $p$ and let $K$ be a cyclic extension of $F$ of degree $p$. Prove that $K=F(\alpha)$ where $\alpha$ is a root of the polynomial $x^p-x-a$ for some $a\in F$.