\begin{frame} \frametitle{References} \scriptsize \begin{itemize} \item Milton Abramowitz and Irene A. Stegun {\em Handbook of Mathematical Functions} 1964: National Bureau of Standards. \item G. N. Watson {\em A Treatise on the Theory of Bessel Functions, 2nd. ed} 1966: Cambridge University Press. \item Marcus J. Grote and Joseph B. Keller ``On Nonreflecting Boundary Conditions" {\em Journal of Computational Physics}, 122, 231 - 243, 1995. \item F. W. J. Olver, {\em The Asymptotic Expansion of Bessel Functions of Large Order}, Phil. Trans. Roy. Soc. Lond. A 247 (1954) 328-368. \item P. K. Chattopadhyay, {\em Mathematical Physics}, 1990: New Age International (P) Limited, Publishers. \end{itemize} \end{frame}