1914  Groth: 525: no indication of locality, only "pyrititic shales of Guadalmez"
     1962  Almela et al.: 41, 43: Between km 298 and 300,, and especially 299,1".
     1999  Montesinos & Sanz-López: 165: Nodules of lower part of Casa de la Vega Fm., "Trinchera del Ferrocarril".