\documentclass{article}
\usepackage{stex}

\title{A Background Theory for our Requirements Document}
\author{Michael Kohlhase\\Jacobs University, Bremen}

\begin{document}
\maketitle

\begin{module}[id=background]
  \symdef{data}{DATA^{tm}} 
  \begin{definition}
    $\data$ is a standard for describing data optimally. Here, {\definiendum{data}} is a
    collection of numbers obtained from a {\definiendum[source]{data source}}.
  \end{definition}
\end{module}

\end{document}

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