%%
%% The LaTeX Companion, 3ed
%%
%% Example 2-4-9 on page I-87 in "cleveref --- Cleverly formatted references".
%%
%% Copyright (C) 2022 Frank Mittelbach
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3c
%% of this license or (at your option) any later version.
%%
%% See https://www.latex-project.org/lppl.txt for details.
%%

\documentclass{tlc3exa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{159.0pt}


  \setcounter{section}{3}

  \usepackage{amsmath}

  \AtEndDocument{%     we place the equations at the document end so that
                 %     they do not show up in the book and take up unnecessary space
    \newpage
    \section{A section}\label{sec:this}
    \begin{align}
      a &= b \label{eq:a} \\
      b &< c \label{eq:b} \\
      c &< d \label{eq:c} \\
      d &< e \label{eq:d} \\
      a &< e \label{eq:e}
    \end{align}
  }

%StartShownPreambleCommands
\usepackage[ngerman,sort]{cleveref}
%StopShownPreambleCommands

\begin{document}
\Cref{eq:c,eq:a,eq:b} in \cref{sec:this} \ldots
\end{document}