\documentclass{article}
\usepackage[paper=letterpaper, text={6.2in,8.5in},centering]{geometry}
\usepackage[colorlinks=True,urlcolor=blue,citecolor=black,breaklinks=true]{hyperref}

\makeatletter
   \renewcommand{\@biblabel}[1]{}
   \renewcommand{\@cite}[2]{{#1\if@tempswa , #2\fi}}
\makeatother

\begin{document}

Lorem \cite{test1} ipsum \cite{test2}.

\bibliography{example9}
\bibliographystyle{example9}

\end{document}

