Bond, David P. G., Beauchamp, Benoit, Blomeier, Dierk, Galloway, Jennifer M., Grasby, Stephen E., Piepjohn, Karsten, Reinhardt, Lutz, Talavera, Cristina, Wignall, Paul, "Progressive environmental deterioration in northwestern Pangea leading to the latest Permian extinction", Geological Society of America bulletin, 2015