1. G. V. Badalyan, Classification and representation of infinitely differentiable functions (Russian), Izv. Akad. Nauk SSSR, Mat. Ser. 34 (1970), 584–620.
2. T. Bang, Om quasianalytiske Funktioner, Thesis, Copenhagen, 1946.
3. A. Beurling, Collected Works, Vol. 1, Complex Analysis, Birkhäuser, Boston, 1989, pp. 396–443.
4. T. Carleman, Les Fonctions Quasianalytiques, Gauthiers-Villars, Paris, 1926.
5. A. Denjoy, Sur les fonctions quasianalytiques d’une variable réele, C. R. Acad. Sci. Paris 173 (1921), 1329.