Came across a few paper written by Janusz Zielinski. He is a Polish geodesist BSc Warsaw (1957) PhD Warsaw (1965) Habilitation Warsaw (1975) Full Professor 1988. Janusz Zielinski Among the publications: Monographs. 1. JB ZIELIŃSKI - Gravity and Low Frequency Geodynamics. Chapters: 1.7 - The Geoid; 1.8 -Gravimetric Reductions, Isostasy and Gravity Anomalies; 2 - Space Geodesy Methods; 8 - Gravity and Reference Models. Ed. R. Teisseyre, PWN, Warsaw / Elsevier - Amsterdam, 1989. 2. JB ZIELINSKI - Earth Size Changes. Geophysical Monograph 60, IUGG, Vol. 10, editors: GDGarland and JRApel, AGU Series 1990; and Geodesy and Cartography, Vol. 27. p.275, 1988. 81. JBZIELIŃSKI - My personal consequences of the 1st sputnik, 50 Year of Space Age Space: The First Step..Ed. Moscow, 2007, SRI RAS, Source - here . - - - - -