Cleal, Cristopher J, y Cedric H Shute. «A New Late Carboniferous Calamitacean Sphenophyte from South Wales, United Kingdom». Spanish Journal of Palaeontology 31, no. 1 (abril 25, 2020): 25–40. Accedido diciembre 11, 2024. https://turia.uv.es/index.php/sjpalaeontology/article/view/17138.