Thanks to visit codestin.com Credit goes to dlmf.nist.gov
where
(14.11.1) holds if 𝖯νμ(x) is replaced by Pνμ(x), provided that the factor ((1+x)/(1−x))μ/2 in (14.11.3) is replaced by ((x+1)/(x−1))μ/2. (14.11.4) holds if 𝖯νμ(x), 𝖯ν(x), and 𝖰ν(x) are replaced by Pνμ(x), Pν(x), and Qν(x), respectively.
See also Szmytkowski (2006, 2009, 2011, 2012), Cohl (2010, 2011) and Magnus et al. (1966, pp. 177–178).