$modus 0:
$modus 1:
Penstemon whippleanus
Penstemon whippleanus A. Gray [Accepted]
Scrophulariaceae Antirrhinoideae Cheloneae
2 764073 Penstemon whippleanus A. Gray
Addisonia, vol. 20 : t. 671 (1938) [M. Sorensen]