Magnetostatic levitation and two related linear PDEs in unbounded domains Constraints and interactions in quantization of Yukawa model with higher-order derivatives A metrical approach to Finsler geometry On the even-indexed eigenfunctions of the Quantum harmonic oscillator Dynamical symmetry of a semiconfined harmonic oscillator model with a position-dependent effective mass Ground state energies of the Hubbard models and the Hartree-Fock approximation An unbounded generalization of Tomita's observable algebras III