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\centerline{\textbf{Recommendations for authors}}

\medskip
We use Overleaf service (overleaf.com) so you can prepare your abstract in the Overleaf online or in any other \LaTeX \, editor. This file has now no errors in Overleaf.

\medskip
This is how your abstract will appear in the table of contents (the page number obviously will be different):

\tableofcontents


%-------- HERE THE TEXT OF YOUR ABSTRACT BEGINS
\newpage
%---------Select exactly one of these sections, other 5 sections should be marked by %. In this example the talk belongs to section "Nonlinear flows and semiflows"

%\addcontentsline{toc}{section}{One-parameter groups and semigroups of linear operators}
\addcontentsline{toc}{section}{Nonlinear flows and semiflows}
%\addcontentsline{toc}{section}{Interplay between linear infinite-dimensional systems and nonlinear finite-dimensional systems}
%\addcontentsline{toc}{section}{Quantum stochastic evolutions and dynamical semigroups}
%\addcontentsline{toc}{section}{Further applications of semigroups in mathematical physics}
%\addcontentsline{toc}{section}{Related topics}


% This line sets how your abstract will appear in the table of contents
\addcontentsline{toc}{subsection}{N.\,I.\,Author, A.\,B.\,Coauthor. Title of your talk}

%Below is the text of your abstract
\begin{center}
\textbf{Title of your talk}

\textbf{N.\,I.\,Author,\footnote{University, Department, Country, City. Another University, Another Department, Another Country, Another City. International Institution.  Email: ni-author@gmail.com} A.\,B.\,Coauthor.\footnote{University, Department, Country, City. Email: abcoauthor@institution.org}}
\end{center}

\small
\smallskip
\textbf{Keywords:} some keyword; another keyword. (3-8 keywords recommended)

\smallskip
\textbf{MSC2010 codes:} 47D08, 35C15, 35J10 (1-5 codes recommended)
\normalsize
\medskip

\textbf{Introduction.} It is known (see [1]) that...

\textbf{Some other subtitle, e.g. Problem setting, Main result, Discussion etc.} Let us consider...

\textit{Theorem 1.} If ... then ... for all $x\in\mathbb{R}$.

Please do not use your own shortcuts for standard constructions, e.g. please use full mathbb command to obtain $\mathbb{C}$ symbol. This will guarantee that all the symbols will appear as they should be.

\textit{Remark 1.} Consider the formula
$$
R(t)=e^{i(S(t)-I)}.\eqno(1)
$$
Please do not use automatic \TeX \, numeration and do not introduce labels and references via those labels. Please use explicit numeration of formulas using eqno command instead, as it is shown in (1). This will make each text self-contained.

\medskip
\textbf{Acknowledgments.} Authors are thankful to ...

\medskip
\textbf{References:} 

[1] E.~Hille, R.S.~Phillips: Functional Analysis and Semi-Groups. --- American Mathematical Society, 1975. \textit{(this is an example of a description of a book)}

[2] C.~Bonatti, V.~Grines, O.~Pochinka. Topological classification of Morse-Smale diffeomorphisms on 3-manifolds // Duke Mathematical Journal. 2019. Vol. 168. No. 13. P. 2507-2558. \textit{(this is an example of a full description of the paper)}

[3] I.~Remizov. Quasi-Feynman formulas -- a method of obtaining the evolution operator for the Schr\"odinger equation // J. Funct. Anal. 270:12 (2016) 4540-4557 \textit{(this is an example of a short description of the paper)}

[4] A.V.~Vedenin, V.S.~Voevodkin, V.D.~Galkin, E.Yu.~Karatetskaya, I.D.~Remizov. Speed of convergence of Chernoff approximations to solutions of evolution equations// arXiv:1910.09440 [math.FA] (2020) \textit{(this is an example of a description of a preprint)}

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Please do not use automatic \TeX \, bibliography via bibitem labels. Please use numeration in square brackets instead, e.g. [6]. This will make each text self-contained.

\vskip1cm
The recommended length of the text is 1-3 pages, from the title of the talk to the last reference. E.g. this sample text has the length equal to one  page. 

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Hope you will enjoy the OPSO Conference :)

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