The species has two varieties:8
NRCS. "Linum medium". PLANTS Database. United States Department of Agriculture (USDA). Retrieved 22 June 2015. /wiki/Natural_Resources_Conservation_Service ↩
Linum medium (Planch.) Britton, USDA PLANTS https://plants.usda.gov/java/profile?symbol=LIME2 ↩
Flora of North America, Linum medium http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=242416770 ↩
Yatskievych, George (2013). Flora of Missouri, Volume 3. Missouri Botanical Garden Press. p. 402. ↩
IllinoisWildflowers http://www.illinoiswildflowers.info/prairie/plantx/st_ylflax.html ↩
Roger Tory Peterson & Margaret McKenny (1996), A field guide to wildflowers : Northeastern and North-central North America, Illustrations by Roger Tory Peterson., Boston: Houghton Mifflin, pp. 164, ISBN 0-395-91172-9 0-395-91172-9 ↩
"Archived copy" (PDF). Archived from the original (PDF) on 2013-04-13. Retrieved 2013-08-23.{{cite web}}: CS1 maint: archived copy as title (link) Pennsylvania DCNR https://web.archive.org/web/20130413065740/http://www.dcnr.state.pa.us/cs/groups/public/documents/document/dcnr_016208.pdf ↩
Alan Weakley (2015). "Flora of the Southern and Mid-Atlantic States". http://www.herbarium.unc.edu/flora.htm ↩