1. L.A.Lockwood, J.Math.Phys. 18, 45 (1977).
2. M.Sato, Prog.Theor.Phys. 13, 405 (1955). Sato has expressed the Racah coefficient symbolically as a bionomial expansion, and in ref. 3, we have shown that there are twelve possible bionomial expansions, depending upon n.
3. K.Srinivasa Rao and K.Venkatesh, Proc. of the Vth Int.Coll. on Gp. Theor.Methods in Phys., Montreal (1976).
4. By setting in eq.1 of ref.3, n=ßk-P, k=1,2,3, in succession, we get the set I of sgries expansions: W(abcd;ef)
(in the notation of ref.3), which is( obviously invariant to permutations of the four 06 's and of two of the three ß's(ßj;j≠k).
5. K.Srinivasa Rao, T.S.Santhanam and K.Venkatesh, J.Math.Phys. 16, 1528 (1975).