Label equation with a symbol
Perhaps something like this.
\documentclass[11pt,a4paper]{article}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{mathtools} % loads »amsmath«
\begin{document}
\begin{equation}\label{eqn:einstein}
E=mc^2\tag{*}
\end{equation}
\eqref{eqn:einstein}
\end{document}
With amsmath
, you have two similar commands:
\tag{label}
where label can be any text or symbol. Note, for most symbol mathmode is required, for example:\tag{$\star$}
. Here the label would be typeset within parentheses.\tag*{label}
, in contrast, does not add parentheses, otherwise it works similar to\tag
.
For further information have a look at the amsmath user's guide.
In addition to the answers about how to \tag
equations with symbols, there are a number of packages that give you access to a bunch more symbols. Like pifont
, ifsym
, MarvoSym
, bbding
See p. 71 et seq. of the Comprehensive LaTeX symbols list for details.
For example:
\documentclass{article}
\usepackage{pifont}
\usepackage{amsmath}
\begin{document}
\[
E=mc^2 \label{eq:einstein} \tag{\ding{37}}
\]
As we can see from \eqref{eq:einstein}\ldots
\end{document}
Produces: