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\renewcommand{\refname}{Bibliography}



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%    Please insert here: first name(s) and surname(s) of the author(s)
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$\blacksquare$ {\bf First author} {\small First author - the abbreviated address, email: {\tt firstauthor@xxxxxxx.xxx}}, 
{\bf Second author} {\small Second author - the abbreviated address, email: {\tt secondauthor@xxxxxxx.xxx}}   
and {\bf Last author} {\small Last author - the abbreviated address, email: {\tt lastauthor@xxxxxxx.xxx}}\\


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{\textit {\large Insert here the title of the talk}} 
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\begin{center} \textbf{Abstract}
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Insert here the text of your abstract. \\


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% the references in the abstract must be complete i.e.: surname(s) and the initial(s) of first name(s) 
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% for a book, year and Publisher as it is below.
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\small  
\begin{thebibliography}{99}

\bibitem{CH}
Courant, R. and Hilbert, D., {\textit{Methods of Mathematical Physics}}, vol. 1, Wiley-VCH Verlag GmbH, Weinheim (2004). 

\bibitem{Nikolskii2008} Nikolskii, S. M., {\textit{A generalization of the fundamental theorem of spherical harmonic theory}}, J. Math. Sci., {\bf 155}, 105-108 (2008).

\end{thebibliography}


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\end{document}
