A.J.Paton, Harley & M.M.Harley (Briq.) 1994 - Paton A, Harley MM, Harley RM, Weeks S (1994) A Revision of Endostemon (Labiatae). Kew Bulletin 49(4): 673-716. doi: 10.2307/4118065.
There is no corrections for Endostemon leucosphaerus yet.