Taxon - Odkazy a literatura
Kew Science - Plants of the World online 2024-05 [60447182-2]
Kew Science - Plants of the World online [https://powo.science.kew.org], Facilitated by the Royal Botanic Gardens, Kew [jako Penstemon labrosus (A.Gray) Mast. ex Hook.f.]
Datum citace: 31. leden 2025
C. Ulloa et al. (2017): An integrated assessment of the vascular plant species of the Americas, Science. 358. 1614-1617 [jako Penstemon labrosus (A. Gray) Hook. f.]Datum citace: 1. duben 2020