Evidence of a Low‐Velocity Zone in the Upper Mantle Beneath Cumbre Vieja Volcano (Canary Islands) Through Receiver Functions Analysis oleh V. Ortega‐Ramos, L. D'Auria, J. L. Granja‐Bruña, I. Cabrera‐Pérez, J. Barrancos, G. D. Padilla, P. Hernández, N. M. Pérez