[1]
W. Stinnesbeck, J. G. López-Oliva, E. Frey, C. Ifrim, and S. Giersch, “The oldest stratigraphic record of the Late Cretaceous shark Ptychodus mortoni Agassiz, from Vallecillo, Nuevo León, northeastern Mexico”, revmexcg, vol. 25, no. 2, pp. 365–366, Jan. 2018.