N.H.Holmgren (D.D.Keck) 1979 - Holmgren NH (1979) Nomenclatural Changes in Some Intermountain Penstemons (Scrophulariaceae). Brittonia 31(1): 104-107. doi: 10.2307/2806680.
There is no corrections for Penstemon angustifolius var. venosus yet.