I need a reference for the following result (different than the Hahn's paper (1907)):
Theorem: If $G$ is an abelian ordered group, then the field $\mathbb{R}((G))$ is archimedean complete.
- $\mathbb{R}((G))$ consists of all the functions $f:G\to\mathbb{R}$ such that $\{g\in G:f(g)\neq0\}$ is well-ordered.
- Let $E$ be an ordered field. Two non-zero elements $x,y\in E$ are comparable if there are $m,n\in\mathbb{N}$ such that $|x|<m|y|$ and $|y|<n|x|$, where $|a|=\max\{a,-a\}$ for every $a\in E$.
- Let $E/ K$ be an extension of ordered fields, where the order on $E$ restricted to $K$ coincides with the order of $K$. We say that $E$ is an Archimedean extension of $K$ if for every $x\in E$, there exists $y\in K$ such that $x$ and $y$ are comparable in $E$.
- A field $K$ is Archimedean complete if there is no proper archimedean extension of $K$.
Someone knows any good references for the proof of this result? The more the better.