On quantum twist maps and spectral properties of Floquet operators Gunther Karner — 1998 Annales de l'I.H.P. Physique théorique
The Schrödinger equation on non-stationary domains. Karner, Gunther — 1998 Electronic Journal of Differential Equations (EJDE) [electronic only]
Irrational numbers of constant type -- a new characterization. Mukherjee, Manash; Karner, Gunther — 1998 The New York Journal of Mathematics [electronic only]