As another example, number R10 denotes the Green's function in a large body containing a cylindrical void (a < r < ∞ ∞ ) with a type 1 (Dirichlet) boundary condition at r = a. Again letter R denotes the cylindrical coordinate system, number 1 denotes the type 1 boundary at r = a, and number 0 denotes the type zero boundary (boundedness) at large values of r. The boundary value problem for the R10 Green's function is given by