On a Theorem of Dedekind

Let $(K,\nu)$ be an arbitrary valued field with valuation ring $R_{\nu}$ and $L=K(\alpha)$, where $\alpha$ is a root of a monic irreducible polynomial $f\in R_{\nu}[x]$. In this paper, we characterize the integral closedness of $R_\nu[\alpha]$ in such a way that extend Dedekind's criterion. Without the assumption of separability of the extension $L/K$, we show that Dedekind's theorem and its converse hold.