Natbib: How to use authoryear style in-text and numbering in the bibliography

I am now writing a project paper which has several citations. My tutor requests me to use(Author, Year) style in text for reference purposes, but the bibliography need to have numbering. How do I achieve a hybrid of both style in natbib package? Thanks!

• Why with natbib? Won't be easier to achieve that with bibilatex? – Aradnix Oct 10 '14 at 5:41
• Any chance you can convince your tutor that his/her requirement is a bad idea, typographically speaking? When using author-year citation callouts, prefixing the entries in the bibliography with numbers is utterly pointless. All the numbers provide in such a case is visual clutter. – Mico Oct 10 '14 at 6:04
• @Aradnix - Just because might be done with some tool doesn't mean that it should be done, right? – Mico Oct 10 '14 at 6:08
• @Mico Right, that's a good point. – Aradnix Oct 10 '14 at 6:14

Actually, when you redefine biblabel to add labels in the reference list, that'll automatically show the number as a label:

\documentclass{article}
\RequirePackage{natbib}
\makeatletter
\renewcommand\NAT@biblabel[1]{[#1]}
\makeatother
\begin{document}

Text \cite{ref}

\bibliographystyle{plainnat}
\bibliography{References}

\end{document}