Christenhusz, M.J.M., Reveal, J.L., Farjon, A., Gardner, M.F., Mill, R.R. and Chase, M.W. 2011. A new classification and linear sequence of extant gymnosperms. Phytotaxa. 19, 1 (Feb. 2011), 55–70. DOI:https://doi.org/10.11646/phytotaxa.19.1.3.