Álvarez-Vázquez, C., Bek, J. y Wagner, R. H. (2018) «Revision and significance of the Westphalian (Middle Pennsylvanian) arborescent lycopsid Bergeria dilatata (Lindley & Hutton) Álvarez-Vázquez & Wagner», Spanish Journal of Palaeontology, 33(1), pp. 5–40. doi: 10.7203/sjp.33.1.13240.