Budaev, V. D. On the unconditional basis property of systems of eigenfunctions and associated functions of a second order operator with discontinuous coefficients. (English. Russian original) Zbl 0632.34018 Sov. Math., Dokl. 34, 141-144 (1987); translation from Dokl. Akad. Nauk SSSR 289, 777-780 (1986). The author studies the unconditional basis property on a closed interval of systems of eigenfunctions and associated functions of the linear nonselfadjoint second order differential operator \(Lu=p_ 0(x)u''+p_ 1(x)u'+p_ 2(x)u,\) whose coefficients, \(p_ 0(x)\) included, have a discontinuity at some point of the basic interval. Reviewer: B.D.Sleeman MSC: 34L99 Ordinary differential operators 47E05 General theory of ordinary differential operators 46B15 Summability and bases; functional analytic aspects of frames in Banach and Hilbert spaces Keywords:unconditional basis property; systems of eigenfunctions; linear nonselfadjoint second order differential operator PDFBibTeX XMLCite \textit{V. D. Budaev}, Sov. Math., Dokl. 34, 141--144 (1987; Zbl 0632.34018); translation from Dokl. Akad. Nauk SSSR 289, 777--780 (1986)