Cleal, Christopher J.; Lazarus, Maureen; Townsend, Annette (2005). Illustrations and illustrators during the 'Golden Age' of palaeobotany: 1800–1840. У Bowden, A. J.; Burek, C. V.; Wilding, R. (ред.). History of palaeobotany : selected essays. London: Geological Society of London. с. 41. ISBN9781862391741.
berkeley.edu
ucmp.berkeley.edu
Speer, Brian R. (10 червня 1995), The Devonian Period, процитовано 12 травня 2012
doi.org
Elgorriaga, A.; Escapa, I.H.; Rothwell, G.W.; Tomescu, A.M.F.; Cúneo, N.R. (2018). Origin of Equisetum: Evolution of horsetails (Equisetales) within the major euphyllophyte clade Sphenopsida. American Journal of Botany. 105 (8): 1286—1303. doi:10.1002/ajb2.1125. PMID30025163.
Elgorriaga, A.; Escapa, I.H.; Rothwell, G.W.; Tomescu, A.M.F.; Cúneo, N.R. (2018). Origin of Equisetum: Evolution of horsetails (Equisetales) within the major euphyllophyte clade Sphenopsida. American Journal of Botany. 105 (8): 1286—1303. doi:10.1002/ajb2.1125. PMID30025163.