Ewan (Munz) 1942 - Ewan J (1942) The Genus Delphinium in North America: Series Echinatae of Subsection Subscaposa, and Miscellaneous Noteworthy Species. Bulletin of The Torrey Botanical Club 69: 137-150. doi: 10.2307/2481449.
There is no corrections for Delphinium patens subsp. montanum yet.