External links to taxonomic opinions:
- IPNI Life Sciences Identifier (LSID)
- urn:lsid:ipni.org:names:179416-1
- Publication
- Reports of explorations and surveys, to ascertain the most practicable and economical route for a railroad from the Mississippi River to the Pacific Ocean
- Collation
- 2: 126
- Family as entered in IPNI
- Asteraceae