\[W_{n,2}(u,\xi)=\xi^{1/2}K_{\nu}\left(u\xi^{1/2}\right)\sum_{s=0}^{n-1}\frac{A_%
{s}(\xi)}{u^{2s}}-\xi K_{\nu+1}\left(u\xi^{1/2}\right)\sum_{s=0}^{n-2}\frac{B_%
{s}(\xi)}{u^{2s+1}}+\xi^{1/2}K_{\nu}\left(u\xi^{1/2}\right)O\left(\frac{1}{u^{%
2n-1}}\right).\]