2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/74790We characterize the reproducing kernel Hilbert spaces whose elements are $p$-integrable functions in terms of the boundedness of the integral operator whose kernel is the reproducing kernel. Moreover, for $p=2$ we show that the spectral decomposition of this integral operator gives a complete description of the reproducing kernel.30 pages, Latex2eFunctional AnalysisMathematical Physicstext