W. Wesley Crump, Jason M. Stettler, Robert L. Johnson, Chris D. Anderson, Sarah Harrison, Lindsey M. Meservey, Mikel R. Stevens (2020)
Flower Color Variation in Jones' Penstemon, Penstemon ×jonesii Pennell (P. eatonii A. Gray × P. laevis Pennell) (Plantaginaceae).
Western North American Naturalist80: 131.
DOI: 10.3398/064.080.0201
Mikel R. Stevens, Robert L. Johnson, Jason M. Stettler, Lindsey M. Meservey, Matthew D. Robbins, Chris D. Anderson, Sydney J. Porter, Nathan J. Ricks, Sarah Harrison (2022)
Taxonomic Delimitations within the Penstemon scariosus Pennell (Plantaginaceae) Complex.
Monographs of the Western North American Naturalist14: .
DOI: 10.3398/042.014.0102