Relative Error Control in Bivariate Interpolatory Cubature
  We describe an algorithm for controlling the relative error in the numerical evaluation of a bivariate integral, without prior knowledge of the magnitude of the integral. In the event that the magnitude of the integral is less than unity, absolute error control is preferred. The underlying quadrature rule is positive-weight interpolatory and composite. Some numerical examples demonstrate the algorithm. 
Justin Steven Calder Prentice
math.NA cs.NA