%%
%% The LaTeX Companion, 2ed (second printing August 2004)
%%
%% Example 2-2-7 on page 29.
%%
%% Copyright (C) 2004 Frank Mittelbach, Michel Goossens,
%%    Johannes Braams, David Carlisle, and Chris Rowley
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3
%% of this license or (at your option) any later version.
%%
%% See http://www.latex-project.org/lppl.txt for details.
%%

\documentclass{ttctexa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{207.0pt}

\makeatletter
\renewcommand\subsection{\@startsection
 {subsection}{2}{0mm}%name, level, indent
 {-\baselineskip}%             beforeskip
 {0.5\baselineskip}%            afterskip
 {\normalfont\normalsize\itshape}}% style
\makeatother

\StartShownPreambleCommands
% redefinition of \subsection shown below
\setcounter{section}{4} % simulate previous
                        % sections
\StopShownPreambleCommands
\begin{document}
\ldots\ some text above.
\subsection{Example of a Section Heading}
The heading is set in normal-sized italic
and the separation from the preceding text
is exactly one baseline. The separation
from the text following is one-half
baseline and this text is not indented.
\end{document}