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06/thebibliography/thebibliography.tex

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+\documentclass[a4paper,10pt]{article}
+\usepackage[utf8]{inputenc}
+
+\title{Example Bibliography:\\\texttt{Computer tools in mathematican's work}}
+\author{Enrique Andrade González}
+
+\begin{document}
+
+\maketitle
+
+\textbf{Thebibliography} environment is native to \LaTeX\ and may be preferred when the document will have few citations, when the document will be edited by different people and coordination becomes difficult, or when a library for \textbf{BibTEX} is not available with the required bibliography and for some reason you do not want to do one. 
+The bibliography should be published directly in the document with the \textbf{thebiblio-graphy} environment, which will be placed where you want the bibliography to appear.
+Each bibliographic entry will be made through the \textbf{\textit{bibitem}} instruction.
+
+For example:
+\newline
+
+This document is an example of \texttt{thebibliography} environment using in bibliography management. Three items are cited: \textit{The \LaTeX\ Companion} book \cite{latexcompanion}, the Einstein journal paper \cite{einstein}, and the Donald Knuth's website \cite{knuthwebsite}. The \LaTeX\ related items are \cite{latexcompanion,knuthwebsite}. 
+\medskip
+
+\begin{thebibliography}{9}
+\bibitem{latexcompanion} Michel Goossens, Frank Mittelbach, and Alexander Samarin. \textit{The \LaTeX\ Companion}. Addison-Wesley, Reading, Massachusetts, 1993.
+\bibitem{einstein} Albert Einstein. \textit{Zur Elektrodynamik bewegter K{\"o}rper}. (German) [\textit{On the electrodynamics of moving bodies}]. Annalen der Physik, 322(10):891–921, 1905.
+\bibitem{knuthwebsite} Knuth: Computers and Typesetting,\\\texttt{http://www-cs-faculty.stanford.edu/\~{}uno/abcde.html}
+\end{thebibliography}
+
+\end{document}