well , do you wish to solve Bessel's equation or use Bessel's function as solution of your PDE.-we do not know!
I remember i used to consult a book on special function by Abramowitch and stegun ,which was a compendium on special functions. for an intro you can also.consult wikipedia
ref;
1. Abramowitz, M. and Stegun, I. A. (Eds.). "Bessel Functions
and http://mathworld.wolfram.com/images/equations/BesselFunctionoftheSecondKind/Inline49.gif." §9.1 in [I][URL='']Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables, 9th printing.[/URL][/I] New York: Dover, pp. 358-364, 1972.
2. [URL]http://mathworld.wolfram.com/BesselFunctionoftheSecondKind.html[/URL]
But G.N. watson 's book on it is very good for theory part
3. Watson, G. N. [I][URL='']A Treatise on the Theory of Bessel Functions, 2nd ed.[/URL][/I] Cambridge, England: Cambridge University Press, 1966.[/QUOTE]I want solve Bessel's equation and use Bessel's function ، How can I get books proposed by please, I do not buy it because it is not available in my country