%%
%% The LaTeX Companion, 3ed
%%
%% Example 3-4-7 on page I-181 in "csquotes --- Context-sensitive quotation marks".
%%
%% 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}

  \setlength\parindent{0pt}     % -- no par indentation for example
  \setlength\leftmargini{1.5em} % -- shorten quote indentation for example

%StartShownPreambleCommands
\usepackage{csquotes} \SetBlockEnvironment{quotation}
%StopShownPreambleCommands

\begin{document}
He said: \begin{displayquote}[Umberto Eco][.]
  Our life is full of empty space
\end{displayquote}
\begin{displayquote}[Douglas Adams]  Space is big.
  You just won't believe how  vastly, hugely,
  mind-bogglingly big [\ldots]
\end{displayquote}
\end{document}
