I'm interested in calculating the assymptotic form of
$K_{i a x}(b x) $
as $x \to \infty$. I looked here (http://dlmf.nist.gov/10.45) but the limits there are taken with the order being fixed (10.45.5) and in my case both the order and the argument go to infinity.
I've tried to look at the references given at the bottom of the page about double assymptotics, but they are behind a paywall. Can somebody help me?