Inverse problem of potential theory

A. G. Ramm

P. Novikov in 1938 has proved that if $u_1(x)=u_2(x)$ for $|x|>R$, where $R>0$ is a large number, $$u_j(x):={\int }_{D_j}{g}_0(x,y)dy,g_0(x,y):=\frac{1}{4\pi |x-y|},$$ and $D_j\subs…