Ronald A. Lovett
Mixing of the Levels of the Hydrogen Atom Due to the Hyperfine Interaction
А. С. Иванов
Hyperfine interaction in a classical hydrogen atom and geometric quantization
Christian Duval, J. Elhadad, Gijs M. Tuynman
Effect of hyperfine interaction on radiative transitions and the polarizability of the hydrogen atom
A. S. Elkhovskii, Iosif B. Khriplovich
A Classical Description of the Hyperfine Structure of the Hydrogen Atom
Andrea Chaney, James M. Espinosa, James R. Woodyard
Geometric quantization and hyperfine structure of hydrogen atom
J. Elhadad
Hyperfine Interactions of Interacting Atoms.
Supriya Ray