[Tex/LaTex] My Bibliography Does Not Appear

Question

The bibliography doesn't appear in the next code, I am exporting the bibliography from a .bib file, the .bib file is a TeX document called sample.bib that I've modified replacing the extension by .bib, besides I've created a document called sample.bib that was a plain text, but the bibliography doesn't appear either.

This is my code.

\documentclass[12pt,a4paper]{book}

\usepackage[utf8]{inputenc}
\usepackage[spanish]{babel}
\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{pgf,tikz}
\usetikzlibrary{arrows}
\usepackage{float}
\usepackage{mathtools}

\DeclarePairedDelimiter\abs{\lvert}{\rvert}%
\DeclarePairedDelimiter\norm{\lVert}{\rVert}

\title{Propuesta de Investigación\\Analisis de bifurcaciónes de Codimension- 2 en un Modelo de Desarrollo sostenible\vspace{5cm}\\}
\author{Juan Pablo Muñoz Diaz\\}
\date{\today}
\begin{document}


\bibliography{sample}

\end{document}

Answer 1

Well, in your code are two errors causing that the bibliography can not be displayed.

The first one is that you have to add an command \bibliographystyle{...} to define the layout of the resulting bibliography, for example you can use \bibliographystyle{unsrt}.

The second error is that you need to cite one or more bib entries to get a bibliography printed. Or you can use command \nocite{*} to get all uncited bib entries printed in the bibliography.

The following code (MWE) compiles with the wanted result:

\RequirePackage{filecontents}
\begin{filecontents*}{\jobname.bib}
@Book{Goossens,
  author    = {Goossens, Michel and Mittelbach, Frank and 
               Samarin, Alexander},
  title     = {The LaTeX Companion},
  edition   = {1},
  publisher = {Addison-Wesley},
  location  = {Reading, Mass.},
  year      = {1994},
}
@Book{adams,
  title     = {The Restaurant at the End of the Universe},
  author    = {Douglas Adams},
  series    = {The Hitchhiker's Guide to the Galaxy},
  publisher = {Pan Macmillan},
  year      = {1980},
}
\end{filecontents*}


\documentclass[12pt,a4paper]{book}

\usepackage[utf8]{inputenc}
\usepackage[spanish]{babel}
%\usepackage{amsmath}
%\usepackage{amsfonts}
%\usepackage{amssymb}
%\usepackage{pgf,tikz}
%\usetikzlibrary{arrows}
%\usepackage{float}
\usepackage{mathtools}

\DeclarePairedDelimiter\abs{\lvert}{\rvert}%
\DeclarePairedDelimiter\norm{\lVert}{\rVert}

\title{Propuesta de Investigación\\Analisis de bifurcaciónes de Codimension- 2 en un Modelo de Desarrollo sostenible\vspace{5cm}\\}
\author{Juan Pablo Muñoz Diaz\\}
\date{\today}


\begin{document}

Text~\cite{adams} % citing one bib entry % <============================
\nocite{*}   % all not cited bib entrys are shown in bibliography ...
\bibliographystyle{unsrt} % <===========================================
\bibliography{\jobname} % to use file created by filecontents ...

\end{document}

with the resulting pdf: