The oblique derivative problem

"The Oblique Derivative Problem is one of the classical problems in the theory of Partial Differential Equations as well as in Mathematical Physics. In a very important particular case the vector field of the problem is tangent to the boundary of a domain on a subset. This case was introduced and studied by Henri Poincare when investigating the tides on the Earth. Apart from this, the problem arises naturally when determining the gravitational fields of the Moon, the Earth and other celestial bodies." "This is the first monograph, written by one of the leading scientists in this area, which is completely devoted to the Oblique Derivative Problem. All the main results in this field are described with full proofs based on modern techniques."--Jacket.