http://www.saber.ula.ve/handle/123456789/4548 1981 Mon, 13 Apr 2026 12:12:16 GMT 2026-04-13T12:12:16Z http://www.saber.ula.ve/handle/123456789/22342 Notas de Matemática Tue, 07 Mar 2006 09:00:00 GMT http://www.saber.ula.ve/handle/123456789/22342 2006-03-07T09:00:00Z http://www.saber.ula.ve/handle/123456789/22341 A note on spectral and prespectral operators. Panchapagesan T., Venkataramaiyer Wed, 10 Aug 2005 09:00:00 GMT http://www.saber.ula.ve/handle/123456789/22341 2005-08-10T09:00:00Z