2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/125089We consider the Goursat problem in the plane for partial differential operators whose principal part is the $p$th power of the standard Laplace operator. The data is posed on a union of $2p$ distinct lines through the origin. We show that the solvability of this Goursat problem depends on Diophantine properties of the geometry of lines on which the data is posed.Analysis of PDEsComplex Variables35A10, 35J05text