James W. Horn; Benjamin W. van Ee; Jeffery J. Morawetz; Ricarda Riina; Victor W. Steinmann; Paul E. Berry; Kenneth J. Wurdack. (2012). Phylogenetics and the evolution of major structural characters in the giant genus Euphorbia L. (Euphorbiaceae). , 63(2), 0–326.
doi:10.1016/j.ympev.2011.12.022
