equation icon  gur = - 1, (191) grr = 1 + 2raa_O_a + r2S + O(r3), (192) 1 [ ( ) 2 ] grA = -- r aa - wab_O_b + --r2Sa + O(r3) _O_Aa, (193) r [ 3 ] AB -1 AB 1- 2 ab A B 3 g = r2 _O_ + 3 r S _O_ a_O_b + O(r ) . (194)