Authors Year Title
Higgins, Wagner-Gentis & Wagner 1964 Basal Carboniferous Strata in Part of Northern León, NW. Spain: Stratigraphy, Conodont and Goniatite Faunas.
Bulletin de la Societé belge de Géologie, Paléontologie, Hydrologie, 72 (2): 205-249, fig.1-5, pl.1-5; Bruxelles.
Wagner-Gentis 1960 On Nautellipsites hispanicus (Foord & Crick).
Est. Geol. Inst "Lucas Mallada", 16: 43-51, fig.1-4; Madrid.