\documentclass[10pt]{jja}
% Include here, if it is necessary, the commands to load the packages that you need.
\begin{document}
\special{papersize=20.6cm,20.6cm}
\mainmatter
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% Author's definitions
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% Include here your \newcommand and \def definitions
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% Paper and author information
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\author{Author 1, Author 2 and Author 3}
\title{Title of the paper}
\affiliation{Author 1,\\
Address, line 1,\\
Address, line 2,\\
Address, line 3.\\
{\tt email}\\ \\
Author 2,\\
Address, line 1,\\
Address, line 2,\\
Address, line 3,\\
{\tt email}\\ \\
Author 3,\\
Address, line 1,\\
Address, line 2,\\
Address, line 3,\\
{\tt email}}
\thanks{Insert here the institutions and organizations that supported the research activity corresponding to the paper.}
\maketitle
% If it is necessary include here a short version for the title of the paper and for the list of authors.
% In that case remove also the % symbol comment mark of the following line.
%\markboth{\em Short list of authors}{\em Short title}
\abstract{Insert here the text of your abstract.}
\keywords{Keyword1, keyword2, ..., keywordn}
% Put here your AMS Classifications instead of the ones of the example with
% the format \classification{primary}{secondary}
\classificationps{41A55}{41A25, 42B35}
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% Body of the paper
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\section{Introduction}
Insert here the text of the paper by using the standard \LaTeX\ commands and environments. Notice that the macro style jja.cls automatically loads the AMS packages. Moreover, some common symbols are already defined as $\RR, \NN, \QQ, \ZZ, \PP, \CC$. Also the usual theorem type environments and the proof environment are implemented by default in the style so you can use without previous definition declarations like
\begin{lemma} This is a lemma
\end{lemma}
\begin{proof}
This is the proof of the lemma.
\end{proof}
\begin{proposition} This is a proposition
\end{proposition}
\begin{theorem} This is a theorem
\end{theorem}
\begin{corollary} This is a corollary
\end{corollary}
The complete list of predefined environments is: algorithm, axiom, case, claim, conclusion, condition, conjecture, corollary, criterion, exercise, lemma, problem, proposition, solution, summary, remark, notation, example, definition.
With respect to the images we ask you to use high quality eps graphics. However if you need to use different formats, please contact us (jja@ujaen.es) to solve the technical questions.
Notice that the width of the initial page may change in the final format.
\subsection{Styles for the bibliographic references}
For the bibliographical references, please see the examples of the different styles for books, papers, proceedings, etc. included in this template. You can cite the references by means of the usual \LaTeX\ command: in the format \cite{ref01} or \cite{ref01,ref02}.
\acknowledgements{Acknowledgements}
It is also available this section type declaration for the acknowledgements. Please, use it at your convenience adjusting the title of the section if you need it.
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% References
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\begin{thebibliography}
\bibitem{ref01} {Bister D. (1997)} \hfill \break
{Ein neuer Zugang f\"ur eine verallgemeinerte Klasse von
Tschebyscheff-Splines}, Dissertation, 15 November 1996, Shaker
Verlag, Aachen.
\bibitem{ref02} {de Boor C. (2001)} \hfill \break
{A Practical Guide to Splines} (revised edition), Springer-Verlag,
New York.
\bibitem{ref03} {Carnicer J.-M. and J.-M. Pe\~na (1996)} \hfill \break
{Total positivity and optimal bases},
in: M. Gasca, C. A. Micchelli (eds.) Total Positivity and its
Applications, Math. Appl. 359, pp.~133--155,
Kluwer Academic Publishers, Dordrecht.
\bibitem{ref04}
{Eisenbud D., M. Green and J. Harris (1996)} \hfill \break
{Cayley-Bacharach theorems and conjectures}, Bull. Amer. Math.
Soc. (N.S.) {33}(3), 295--324.
\bibitem{ref05}
{Hakopian H. (2004)} \hfill \break {The multivariate fundamental
theorem of Algebra, Bezout's theorem and Nullstellensatz}, in: D.
K. Dimitrov et al. (eds.) Approximation Theory: a volume dedicated
to Borislav Bojanov, pp.~73--97, Marin Drinov Acad.~Publ.~House,
Sofia.
\bibitem{ref06} {Karlin S. J. and W. J. Studden (1966)} \hfill \break
{Tchebycheff Systems: with applications in analysis and
statistics}, Wiley Interscience, New York.
\bibitem{ref07} {Koch P. E. and T. Lyche (1991)} \hfill \break
{Construction of exponential tension B-splines of arbitrary
order}, in: P.-J. Laurent, A. Le M\'ehaut\'e, L.~L. Schumaker
(eds.) Curves and Surfaces, pp.~255--258, Academic Press, Boston.
\bibitem{ref08} {Mazure M.-L. (2005)} \hfill \break
{Chebyshev spaces and Bernstein bases}, Constr. Approx. {22}(3),
347--363.
\bibitem{ref09} {Mazure M.-L. (2006)} \hfill \break
{Ready-to-blossom bases in Chebyshev spaces}, in: K. Jetter, M.
Buhmann, W. Haussmann, R. Schaback, J.~Stoeckler (eds.) Topics in
Multivariate Appro\-ximation and Interpolation, pp.~109--148,
Elsevier, Amsterdam.
\bibitem{ref10} {Mazure M.-L. and H. Pottmann (1996)} \hfill \break
{Tchebycheff curves}, in: M. Gasca, C. A. Micchelli (eds.) Total
Positivity and its Applications, Math. Appl. 359, pp.~187--218,
Kluwer Academic Publishers, Dordrecht.
\bibitem{ref11}
{M\"oller H. M. (1980)} \hfill \break {Linear abh\"angige
Punktfunktionale bei zweidimensionalen Inter\-po\-la\-tions- und
Approximations\-problemen}, Math.~Z. {173}(1), 35--49.
\bibitem{ref12} {Prautzsch H., W. Boehm and M. Paluszny (2002)}
\hfill \break {B\'ezier and B-splines techniques}, Mathematics and
Visualization, Springer-Verlag, Berlin.
\end{thebibliography}
\end{document}