Bessel functions Boundary value problems 6 Mathematical models 6 Theorem proving 6 Boundary conditions 4 Eigenvalues and eigenfunctions 4 Nonlinear boundary conditions 4 Problem solving 4 Sobolev trace embedding 4 Dirac delta 2 Euclidean space 2 Hankel transforms 2 Integral equations 2 Mathematical transformations 2 Multiplicative products 2 Set theory 2