Willi Freeden is a professor in the Geomathematics Group at the University of Kaiserslautern. Dr. Freeden is an editorial board member of seven international journals and was previously the editor-in-chief of the International Journal on Geomathematics. His research interests include special functions of mathematical (geo)physics, PDEs, constructive approximation, integral transforms, numerical methods, the use of mathematics in industry, and inverse problems in geophysics, geodesy, and satellite technology. Christian Gerhards is a visiting postdoc researcher in the Department of Mathematics and Statistics at the University of New South Wales.

• PRELIMINARIES: Three-Dimensional Euclidean Space R3. Two-Dimensional Sphere O. POTENTIAL THEORY IN THE EUCLIDEAN SPACE R3: Basic Concepts. Gravitation. Geomagnetism. POTENTIAL THEORY ON THE UNIT SPHERE O: Basic Concepts. Gravitation. Geomagnetics. Bibliography. Index.