\documentclass{amsart}
\usepackage{amsmath}
%\usepackage[all]{xy}
\usepackage{tikz}
\begin{document}
  \[
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\documentclass{article}


\title{Google Matrix, PageRank and HITS}
\author{F, Z}

\usepackage{graphicx}
\usepackage{booktabs}
\usepackage{lipsum}


\begin{document}
...
\end{document}

\makeatletter
\let\@oddfoot\relax
\def\@oddfoot\empty
\makeatother

\def\@oddfoot{\footnotesize\itshape
       Preprint submitted to \ifx\@journal\@empty Elsevier
       \else\@journal\fi\hfill\today}%
     \let\@evenfoot\@oddfoot}

\let\@oddfoot\relax
\def\@oddfoot\empty

  \def\pprinttitle{}

\long\def\pprinttitle{
longish list of things
}

\documentclass{article}


\title{Google Matrix, PageRank and HITS}
\author{Gigili}

\usepackage{graphicx}
\usepackage{booktabs}
\usepackage{lipsum}


\begin{document}

 \textbf {Why is Google results different from other search engines?}

\vspace{5 mm}

The web is:
\begin{itemize}
\item Huge ($10^{10} - 10^{11}$ pages on surface; many more in the deep web)
\item Dynamic ($40\%$ changes within a week)
\item Self organized (no central administration)
\item Hyperlinked (linkanalysis can be used to find a relevant item)

Frasier: Yes, we Crane boys sure know how to marry. [goes to the
         kitchen] Let me get you a beer, Dad.  So, ah, what do you
         think of what I've done with the place, eh? [returns and
         sits on the couch, handing a beer to Martin] You know, every
         item here was carefully selected.  This lamp by Corbusier,
         the chair by Eames, and this couch is an exact replica of
         the one Coco Chanel had in her Paris atelier.
 Martin: Nothing matches.
Frasier: Well, it's a, it's a style of decorating, it's called

 Colophon
This thesis is typeset with LATEX2". The font used for the text is URW Garamond Adobe Type-1
font, based on the design of Claude Garamond (1499-1561). The italic fonts were designed by
Robert Granjon (1530-1589). The figures are typeset using TikZ.
Information on how to download the (free) font package is located at this site: http://
www.ctan.org/pkg/urw-garamond. Further information about the URW Garamond font can be
found here: tex.ac.uk/tex-archive/fonts/mathdesign/MD-urw-garamond-doc.

[enrico2013] ~ > pdftex --version
pdfTeX 3.1415926-2.5-1.40.14 (TeX Live 2013)
kpathsea version 6.1.1
Copyright 2013 Peter Breitenlohner (eTeX)/Han The Thanh (pdfTeX).
There is NO warranty.  Redistribution of this software is
covered by the terms of both the pdfTeX copyright and
the Lesser GNU General Public License.
For more information about these matters, see the file
named COPYING and the pdfTeX source.
Primary author of pdfTeX: Peter Breitenlohner (eTeX)/Han The Thanh (pdfTeX).
Compiled with libpng 1.6.1; using libpng 1.6.1

[enrico2013] ~ > xetex --version
XeTeX 3.1415926-2.5-0.9999.2-2013041118 (TeX Live 2013)
kpathsea version 6.1.1
Copyright 2013 SIL International and Jonathan Kew.
There is NO warranty.  Redistribution of this software is
covered by the terms of both the XeTeX copyright and
the Lesser GNU General Public License.
For more information about these matters, see the file
named COPYING and the XeTeX source.
Primary author of XeTeX: Jonathan Kew.
Compiled with ICU version 51.1; using 51.1
Compiled with zlib version 1.2.7; using 1.2.7

\ProvidesPackage{songs}
  [2012/03/17 v2.14 Songs package]