2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/77147The differential operators pencil recovery uniqueness theorem is proved in our article. Novelty of this result is not equation coefficient recovery, but boundary conditions coefficients recovery. We show that all conditions of the theorem are essential. We also give some interesting examples.AmSTeX, version 2.1, 8 pages, amsppt styleSpectral TheoryAnalysis of PDEs47A10text