2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/219473A second-order PDE is derived from Euler's equaitons under certain assumptions. It is shown that this PDE admits shock and rarefaction waves, and that a single point gradient blow-up admits a unique similarity extension after blow-up that settles uniqueness/entropy issues for such equations.16 pages, 8 figuresAnalysis of PDEs35K55, 35K65On blow-up shock waves for a nonlinear PDE associated with Euler equationstext