1. G.G. STOKES: “On the Variation of Gravity at the Surface of the Earth” Transactions of the Cambridge Philosophical Society. vol. 8, pp. 672–695 (1849).
2. F.A. VENING-MEINESZ: “A Formula Expressing the Deflection of the Plumb Line in the Gravity Anomalies and some Formulae for the Gravity Field and the Gravity-potential outside the Geoid”, Koninklije Akademie, van Wetenschappen te Amsterdam, Proceedings Vol. XXXI, No. 3 (1928).
3. L. de WITTE: “Truncation Errors in the Stokes and Vening Meinesz Formulae for Different Order Spherical Harmonic Gravity Terms”. In print: Geophysics Journal, Royal Astronomical Society.
4. M.S. MOLODENSKII, V.F. EREMEEV, and M.I. YURKIMA: “Methods for Study of the External Gravitational Field and Figure of the Earth” Translated from the Russian by the Israel Program for Scientific Translation, Jerusalem 1962.
5. L. de WITTE: “Truncation Errors in the Vertical Extension of Gravity Anomalies by Poisson’s Integral Theorem”. Bulletin Géodésique No. 83, pp. 41–53 (March 1967).