How to use underscore in Bibtex

Suppose we have two files: the main file name is main.tex and xbib.bibtex file.

The main.tex file contains:

\documentclass[11pt]{article}

\begin{document}

The common properties include\cite{internet1}.

\bibliography{xbib}{}

\bibliographystyle{plain}

\end{document}

The xbib.bibtex file contains:

@MISC{internet1,

  howpublished = {\url{http://www.cse.iitm.ac.in/~sdas/courses/CV_DIP/PDF/lect-Segmen.pdf}},

}

Then it will create a problem like:

! Missing $ inserted.     $

The solution is to add the red colored line in main.tex file as follows:

\documentclass[11pt]{article}

\usepackage{underscore}

\begin{document}

The common properties include\cite {internet1}.

\bibliography{xbib}{}

\bibliographystyle{plain}

\end{document}

The xbib.bibtex file should add the red colored portion:

@MISC{internet1,

  howpublished = {\url{http://www.cse.iitm.ac.in/~sdas/courses/CV\textunderscore_DIP/PDF/lect-Segmen.pdf}},

}