For ,
where
and is the smallest of the numbers , , .
For these and further results see Luke (1969b, §9.4.5), and §10.23(iii).
where denotes either or .
For derivatives with respect to the order , see Apelblat (1989) and Brychkov and Geddes (2005).
For properties of zeros of see Steinig (1970).
For asymptotic expansions of zeros of see MacLeod (2002a).