Aguirre Urreta M.B., Vennari R. (2009) On Darwin’s footsteps across the Andes: Tithonian-Neocomoan fossil invertebrates from the Piuquenes Pass // Revista de la Asociacion Geologica Argentina. V.64. no.1. P.32-42. Pdf: http://www.scielo.org.ar/pdf/raga/v64n1/v64n1a05.pdf
The aim of this work is to summarize the modern knowledge of the geology of the Piuquenes Pass, in the Main Andes of Argentina and Chile, and to describe a small fauna of Tithonian-Neocomian invertebrates mostly represented by ammonites. The present knowledge of the region is compared with Darwin's, as expressed in his famous book on the Geology of South America.