Cylindrical oscillations of force-free electromagnetic fields

This paper is devoted to Force-Free Electromagnetic Oscillations in a constant magnetic field. A correction is made in the derivation of the basic equation. The paper confirms the predicted spectrum of frequencies, namely _n = _o(n + 1)^1/2;n = 0, 1, 2, .... In addition it is suggested that hybrid frequency _n = (_n² + _H²)^1/2 should be found in observational data.