Hello, could you help me to understand the next error? texmaker (Mac) [duplicate]

This is the error!:

Overfull \hbox (12.10773pt too wide) in paragraph at lines 13--19

I don´t understand it! It has apareces when i try to compilate with the next document:

\documentclass[11pt]{book}
\usepackage[utf8]{inputenc}
\usepackage[spanish,mexico]{babel}
\usepackage[T1]{fontenc}
%\usepackage{amsmath}
%\usepackage{amsfonts}
%\usepackage{amssymb}
%\usepackage{graphicx}
\usepackage{apacite}

\title{Manual de estrategias psicopedagógicas en el manejo de grupo desde la perspectiva sociocultural}
\author{Itzel Viridiana Gutiérrez Ruiz\\Mayra Yurieth Hernández Robledo}
\date{}
\begin{document}
\frontmatter
\maketitle
%\tableofcontents
%\mainmatter
\include{introduccion}
\backmatter
\bibliographystyle{apacite}
\bibliography{bibliografia}
\end{document}


marked as duplicate by Werner, user13907, Svend Tveskæg, user31729, MasroorAug 27 '14 at 23:53

• Yesterday it compiled well despite the large title, that was not a problem. I fear the problem is inside the other file you load with \include. Perhaps inside there is something wrong that avoid to compile. As @ChristianHupfer says, what you show us is not an error, simply a warning. Please edit your questions and let us see the content of the file introduccion and search the error. – Aradnix Aug 27 '14 at 22:38