%%
%% The LaTeX Companion, 3ed
%%
%% Example 12-3-10 on page II-243 in "Some peculiarities of the Euler fonts".
%%
%% 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{183.0pt}
%StartShownPreambleCommands
\usepackage{ccfonts,eulervm}
%StopShownPreambleCommands

\begin{document}
Compare: $ a + b \neq \mathbf{a} + \mathbf{b}
             \neq \mathbold{a} + \mathbold{b}$
\end{document}