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    testphase={phase-III,table,title,firstaid}
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\documentclass{article}

\usepackage{amssymb,amsmath,upgreek}
\usepackage{tagpdf}


\begin{document}
\title{Coupled spin-orbital fluctuations in a unified approach}
\author{Shubhajyoti Mohapatra and Avinash Singh}

\maketitle

\begin{abstract}
Abstract text
\end{abstract}


\section{Introduction}
Para  1
\section{Test 2}

Para  2

\subsection{Test 2.1}

Para 2.1
\subsubsection{Test 2.2}

Para  2.2

\paragraph{Test 2.3}

Para 2.3

\section{Test 3}

Para 3

\end{document}