Izvekov I. G.
Ukr. Mat. Zh. - 1993. - 45, № 12. - pp. 1622–1626
Classical spaces of ultradifferentiable functions on [?1,1] are compared with the Gevrais classes of a self-adjoint differential operator whose eigenfunctions are orthogonal Jacobi polynomials.
Localization principle for expansions of generalized functions with respect to the eigenfunctions of the Sturm-Liouville operator on a finite interval
Ukr. Mat. Zh. - 1991. - 43, № 5. - pp. 703–706