D.Wilken & R.L.Hartman (Brand) 1991 - Wilken D, Hartman RL (1991) A Revision of the Ipomopsis spicata Complex (Polemoniaceae). Systematic Botany 16: 143-161. doi: 10.2307/2418979.
There is no corrections for Ipomopsis spicata subsp. orchidacea yet.