For p odd, the Lie group SO_0(p+1,p+1) has a family of unitary degenerate
principal series representations realized on the space of real (p+1) by (p+1)
skew symmetric matrices, similar to the Stein's complementary series for
SL(2n,C) or Speh's representation for SL(2n,R). We consider their restriction
on the subgroup G= SO(p+1,p) and prove that they are still irreducible and is
equivalent to (a unitarization of) the principal series representation of G,
and also irreducible under a maximal parabolic subgroup of G.