Flora of the Pacific Northwest, Hitchcock and Cronquist, Univ. of Washington Press,
7th printing, 1990.
Seed Germination Theory and Practice, 2nd Edition, Deno, Norman, publ.1993.
Glacier Park Native Plant Nursery Propagation Records, unpublished.
Seeding Rate Statistics for Native and Introduced Species, National Park Service,
Hassell, Wendel, April 1996.
Seeds: Ecology, Biogeography, and Evolution of Dormancy and Germination, Baskin and Baskin, Academic press, 1998.