2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/107546We give sharp regularity conditions, ensuring the backward uniquess property to a class of parabolic operators.10 pages; to appear in "Phase Space Analysis of PDE's. Proceedings of the Workshop held in Pienza (Italy), November 8-13, 2005"Analysis of PDEs35A05text