@inbook{Echinoidea:SourceID:176086, author = {Smith, A. B. and Gallemí, J. and Jeffery, C. H. and Ernst, G. and Ward, P. D.}, journal = {Bulletin of the Natural History Museum, Geology Series}, pages = {81-137}, title = {Late Cretaceous-early Tertiary echinoids from northern Spain: implications for the Cretaceous-Tertiary extinction event}, url = {https://marinespecies.org/echinoidea/aphia.php?p=sourcedetails&id=176086}, volume = {55}, year = {1999} }