Have the item’s numbering in Roman Upper-case (Capital form, i.e. I, II, III)

Question

I have a theorem with different items in Roman numbers

I want to have the item's numbering in Upper-case (Capital form, i.e. I, II, III)

How can I do this in the given code?

\documentclass[12pt]{article}
\usepackage{enumitem}
\usepackage{amsmath}
\usepackage{amsthm}
\newenvironment{thmenum}
 {\begin{enumerate}[label=\upshape(\arabic*),ref=\thethm(\arabic*)]}
 {\end{enumerate}}
\newtheorem{thm}{Theorem}

\begin{document}



\begin{thm}
We have:
\begin{enumerate}[label=\textnormal{(\roman*)}]
\item \label{th1} abcd.
\item \label{th2} abcd.
\item \label{th3} abcd.
\end{enumerate}
\end{thm}



I want to have \ref{th1}-\ref{th3} in Upper-case form (I,II,III).

\end{document} 

Answer 1

Use a capital R in \Roman :

\documentclass{article}
\usepackage{enumitem}

\begin{document}
\begin{enumerate}[label=\textnormal{(\Roman*)}]
\item \label{th1} abcd.
\item \label{th2} abcd.
\item \label{th3} abcd.
\end{enumerate}
\end{document}