Key to the genus Penstemon and its related genera in the tribe Chelonea
Subtitle: including Chelone, Chionophila, Keckiella, Nothochelone and Pennellianthus (family Scrophularaceae)
By: Robin and Kenneth Lodewick
Contributors: Lodewick, Kenneth
Publisher: R. and K. Lodewick
Published: 1999
Place of publication: Eugene, Or. (2526 University St., Eugene 97403)
Language: eng
Number of pages: 136
Subjects: Penstemons