1. On the existence of electromagnetic-hydrodynamic waves;Alfvén;Nature,1942
2. Wireless studies of the ionosphere;Appleton;J. Inst. Elect. Engrs.,1932
3. On waves in an ionized gas;Åström;Ark. Fys.,1950
4. Plane waves in an ionized gas with static electric and magnetic fields present;Bailey;Aust. J. Sci. Res. A,1948