1. J. D. Fedorenko,A formula for the approximate evaluation of double integrals, (Ukrainian), Dopovidi Akad. Nauk Ukrain, RSR, (1964), 1000–1005.
2. W. Gröbner,Über die Konstruktion von Systemen orthogonaler Polynome in ein-und-zwei dimensionalen Bereiche, Monatsh. Math., 52 (1948), 48–54.
3. L. C. Hsu,On a method for expanding multiple integrals in terms of integrals in lower dimensions, Acta Math. Acad. Sci. Hungar., 14 (1963), 359–367.
4. L. C. Hsu, T. X. He,On the minimum estimation of the remainders in dimensinality lowering expansions with algebraic precision, (Chinese, English summary), J. Math. (Wuhan), (2, 3, 1982) 247–255.
5. L. C. Hsu, J. X. Yang,Dimensionality reducing expansions and boundary type cubature formulas having higher algebraic precision, (Chinese, English summary), Numer. Math. J. Chinese Univ., 3, 4 (1981) 361–369.