  We study Okada's conjecture on $(q,t)$-hook formula of general $d$-complete
posets. Proctor classified $d$-complete posets into 15 irreducible ones. We try
to give a case-by-case proof of Okada's $(q,t)$-hook formula conjecture using
the symmetric functions. Here we give a proof of the conjecture for birds and
banners, in which we use Gasper's identity for VWP-series ${}_{12}W_{11}$.
