LaTeX Forum

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@article{DBLP:journals/jgaa/Tantau13,
  author    = {Till Tantau},
  title     = {Graph Drawing in TikZ},
  journal   = {J. Graph Algorithms Appl.},
  volume    = {17},
  number    = {4},
  pages     = {495--513},
  year      = {2013},
  url       = {http://dx.doi.org/10.7155/jgaa.00301},
  doi       = {10.7155/jgaa.00301},
}
@book{DBLP:books/aw/Knuth86,
  author    = {Donald E. Knuth},
  title     = {The TeXbook},
  publisher = {Addison-Wesley},
  year      = {1986},
  isbn      = {0-201-13447-0},
}
\end{filecontents}

\begin{document}
\cite{DBLP:books/aw/Knuth86,DBLP:journals/jgaa/Tantau13}

\bibliography{\jobname}
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@article{DBLP:journals/jgaa/Tantau13,
  author    = {Till Tantau},
  title     = {Graph Drawing in TikZ},
  journal   = {J. Graph Algorithms Appl.},
  volume    = {17},
  number    = {4},
  pages     = {495--513},
  year      = {2013},
  url       = {http://dx.doi.org/10.7155/jgaa.00301},
  doi       = {10.7155/jgaa.00301},
  timestamp = {Mon, 20 Jan 2014 18:16:05 +0100},
  biburl    = {http://dblp.uni-trier.de/rec/bib/journals/jgaa/Tantau13},
  bibsource = {dblp computer science bibliography, http://dblp.org}
}
@book{DBLP:books/aw/Knuth86,
  author    = {Donald E. Knuth},
  title     = {The TeXbook},
  publisher = {Addison-Wesley},
  year      = {1986},
  isbn      = {0-201-13447-0},
  timestamp = {Thu, 03 Jan 2002 11:51:07 +0100},
  biburl    = {http://dblp.uni-trier.de/rec/bib/books/aw/Knuth86},
  bibsource = {dblp computer science bibliography, http://dblp.org}
}

LaTeX Warning: Citation `DBLP:books/aw/Knuth86' on page 1 undefined on input line 28.

LaTeX Warning: Empty `thebibliography' environment on input line 3.

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\begin{document}
\section{Another \LaTeX example}
\subsection{Bibliography}
You will find the required the Bib\TeX snippets to create the references [Knu86] and [Tan13], with a simple search on \u http://dplp.uni-trier.de/db/.
\subsection{Euclid's Proof of the Infinitude of Primes}
$\textbf{Theorem}$~~ There are infinitely many primes.
\\$\textbf{Proof}$~~by contradiction. Assuming the set $\mathcal{P}$ of primes would be finite, let $\mathcal{P}$ = $\lbrace p_{1},p_{2},\ldots,p_{n}\rbrace$.
\\Now we use the product of all primes: $$ q:= 1+\prod^{n}_{i=1}p_{i}=1+\lbrace p_{1},p_{2},\ldots,p_{n}\rbrace$$
\\Now $\textit{q}$ is a new prime number not in $\mathcal{P}$. So there's a prime $\textit{r}$ that divides $\textit{q}$. But $\textit{r}\epsilon$ $\mathcal{P}$ either, since 
$$ \forall \textit{r}, \textit{r} ~\epsilon~\mathcal{P}  \Rightarrow  q ~mod~ \textit{r} = 1$$
\\ So $\textit{r}$ is a $\textit{new}$ prime number not in $\mathcal{P}$, contradicting the assumption. 
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$\square$
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\bibliography{References}
\cite{DBLP:books/aw/Knuth86}
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