equation icon  ( integral ) 1- 4 4 V~ ------ V~ ------ abcd exp - 8 d x d y - g(x) -g(y) [hab(x)] N (x,y)[hcd(y)] = integral ( integral V~ ------ ) DqP[q] exp i- d4x - g(x)qab(x) [hab(x)] , (25) 2