How to make footnotes have a single margin [duplicate]

Question

I have the following simplified code:

\documentclass[12pt]{article}
\begin{document}
    \section{introduction}
    section one\footnote{book number one} is created\footnote{This is a long sentence
    This is a long sentence This is a long sentence This is a long sentence This is a long
    sentence This is a long sentence This is a long sentence This is a long sentence } And
    then there is the other reference and then there\footnote{book number two} is that one
    and then that one and then there is that one and then that one and then there is that
    one\footnote{book number three} and then that one
\end{document}

The footnotes resulting from this look like this:

How can I make them have the same margin, just like in this photo?

Answer 1

Please try with:

\documentclass[12pt]{article}
\usepackage[hang]{footmisc}
\begin{document}
    \section{introduction}
    section one\footnote{book number one} is created\footnote{This is a long sentence
    This is a long sentence This is a long sentence This is a long sentence This is a long
    sentence This is a long sentence This is a long sentence This is a long sentence } And
    then there is the other reference and then there\footnote{book number two} is that one
    and then that one and then there is that one and then that one and then there is that
    one\footnote{book number three} and then that one
\end{document}