\documentclass[final,leqno,letterpaper]{etna}

\setbibdata{1}{xx}{46}{2017} %First page/Last page/volume/year

\hypersetup{%
    pdftitle={Document title},
    pdfauthor={John Doe, Erwin Schr\"odinger},
    pdfsubject={Document subject},
    pdfkeywords={a keyword, another keyword, and another one}
    }

\title{Paper's title\thanks{%
Received... Accepted... Published online on... Recommended by....
% optional here: Work supported by ...
}}

\author{First author's name\footnotemark[2]
        \and Second author's name\footnotemark[3]}

\shorttitle{SHORT TITLE} 
\shortauthor{F.~FIRSTA AND S.~SECONDA}

\begin{document}

\maketitle

\renewcommand{\thefootnote}{\fnsymbol{footnote}}

\footnotetext[2]{First author's address.}
\footnotetext[3]{Second author's address.}

\begin{abstract}
Paper's abstract.
\end{abstract}

\begin{keywords}
paper's key words, non-capitalized except for names
\end{keywords}

\begin{AMS}
AMS subject classifications
\end{AMS}

\section{First section} This is typically the paper's Introduction.
...
\end{document}
.