00310nam a2200097Ia 450000500170000000800410001708200160005810000200007424500520009426000660014620250107154740.0241216s9999||||xx |||||||||||||| ||und||  aREF 526 GRA  aGrafarend, Erik 0aThree dimensional geodesy and gravity gradients  aColumbusbThe Ohio State University Research Foundationc1972