1. A reexamination of the Potsdam Absolute Determination of Gravity;Dryden;J. Res. NBS,1942
2. Gravity and elevation changes in the Travale geothermal field (Tuscany-Italy);Geri;Geothermics,1982
3. Consideration about gravity and elevation changes observed in the Travale geothermal field;Geri,1983
4. The figures of the earth and moon;Jeffreys,1948